Pancreas Flashcards

Question

What are the 4 types of acute pancreatitis complications per the revised Atlanta Classification?

Answer 1

1. Acute peripancreatic fluid collection or post-necrotic pancreatic/peripancreatic fluid collection. Both occur within 4 weeks and are subclassified as sterile or infected. 2. Pancreatic pseudocyst or walled-off pancreatic necrosis. Both occur after 4 weeks and are subclassified as sterile or infected. (Use of the terms acute pseudo cyst and pancreatic abscess is now discouraged.)

Answer 2

Expectant, supportive management for 4 to 6 weeks If no resolution occurs, wait until a thick, fibrous wall has formed and perform internal cyst drainage via an open or endoscopic cystgastrostomy, cystojejunostomy, or cystduodenostomy A biopsy should always be performed to rule out malignancy. External drainage may be pursued for infected collections of pseudocysts.

Answer 3

4 to 6 weeks

Answer 4

Pseudocyst has not resolved by 6 weeks and persistently greater than 6 cm

Answer 5

Cystogastrostomy, cystoduodenostomy, Roux-en-Y cystojejunostomy, lateral pancreaticojejunostomy

Answer 6

Well-demarcated areas of nonenhancing pancreatic tissue > 3 cm or occupying more than 30% of the gland

Answer 7

CT-guided percutaneous fine needle aspiration

Answer 8

Open or video-assisted retroperitoneal debridement (VARD)

Answer 9

Imipenem or meropenem

Answer 10

Continue nonoperative management

Answer 11

NPO, IV hydration, TPN, electrolyte replacement, and skin care. Somatostatin has not been shown to accelerate closure rate. If no resolution, an endoscopic retrograde cholangiopancreatography (ERCP) to evaluate anatomy and ultimate surgical internal drainage or distal resection.

Answer 12

It usually is due to erosion of an arterial pseudoaneurysm secondary to pseudocyst or necrotizing pancreatitis. Diagnosis is by angiography. Immediate surgery is indicated should the patient become unstable. Selective embolization may be possible in stable patients.

Answer 13

Pancreas divisum

Answer 14

Serous cystadenoma. These tumors have a low rate of malignant transformation.

Answer 15

Resection is generally recommended, but this lesion can be closely followed in high-operative-risk patients

Answer 16

Serous cystadenoma

Answer 17

< 5% in general. Recent reports have cited a 5-year survival of 20% to 25%.

Answer 18

4to 6months

Answer 19

Cigarette smoking

Answer 20

Abdominal pain, jaundice (could be painless jaundice, but this is actually more commonly associated with ampullary and duodenal neoplasms), and weight loss

Answer 21

Ultrasound to evaluate biliary anatomy, contracted CT scan

Answer 22

``` MEN Hereditary pancreatitis Familial Adenomatous Polyposis Hereditary Non-Polyposis Colorectal Cancer Von Hippel-Lindau and Gardner syndromes ```

Answer 23

CA 19-9 (sensitivity 83%, specificity 82%), | CEA (sensitivity 56%, specificity 75%)

Answer 24

Endoscopic ultrasonography

Answer 25

The 2 most active agents are 5-fluorouracil and gemcitabine. Mitomycin C, streptozocin, doxorubicin, and lomustine have also been used. 5- FU potentiates radiation therapy.

Answer 26

Erlotinib (Tarceva)

Answer 27

Tumor limited to the pancreas, <2 cm

Answer 28

Tumor limited to the pancreas, >2 cm

Answer 29

Tumor extends beyond the pancreas but without involvement of the celiac axis or the SMA

Answer 30

Tumor involves the celiac axis or the SMA

Answer 31

T4, by definition

Answer 32

End-to-side pancreaticojejunostomy, hepaticojejunostomy, gastrojejunostomy

Answer 33

Mucinous cystic neoplasm rarely communicates with the main pancreatic duct

Answer 34

Yes. because of malignant potential

Answer 35

Necrolytic migratory erythema

Answer 36

Alpha cells Glucagonomas are usually malignant and metastatic at diagnosis. Tx: Debulking surgery

Answer 37

Elevated plasma glucagon >150 pg/mL (many will have levels in excess of 500 pg/mL)

Answer 38

Verner Morrison syndrome

Answer 39

Watery diarrhea, hypokalemia, and achlorhydria

Answer 40

Ultrasound, CT (often tumor is 3 cm or larger), angiography, and transhepatic venous sampling may be used as second-line in difficult cases Often found at the tail

Answer 41

Enucleation or surgical resection, depending on location | Debulking as palliative treatment

Answer 42

In the gastrinoma triangle, the borders are the pancreatic neck/body junction, confluence of cystic and common hepatic ducts, and the junction of second and third portions of the duodenum

Answer 43

C-peptide:insulin ratio is 1:1 in insulinoma

Answer 44

Whipple Triad: 1) symptoms of hypoglycemia with fasting 2) blood glucose <50 mg/dL 3) relief with glucose intake

Answer 45

72-hour fast. Insulin and glucose are measured every 6 hours. Symptoms of hypoglycemia develop in 12 hours. Insulin:glucose ratio >0.3 or serum insulin >6 µU/mL is diagnostic.

Answer 46

Enucleation Exceptions: 1) Close to the main pancreatic duct 2) >2cm - -> Whipple procedure

Answer 47

Diabetes Dermatitis DVT Depression

Answer 48

Vasoactive intestinal peptide

Answer 49

Octreotide

Answer 50

Somatostatinoma

Answer 51

Octreotide scan

Answer 52

Gastrinoma

Answer 53

Insulinoma

Answer 54

Distal pancreatectomy

Answer 55

Whipple procedure

Answer 56

Somatostatin receptor

Answer 57

A. IV fluid and electrolyte therapy

Answer 58

B. Longitudinal pancreaticojejunostomy

Answer 59

C. Fibrotic stricture of the CBD

Answer 60

B. Microscopic tumor cells in the greater omentum on frozen section

Answer 61

D. Choledochojejunostomy

Answer 62

D. Pancreatic mucinous cystadenoma

Answer 63

D. Resection

Answer 64

E. Protime determination

Answer 65

B. ERCP and biopsy

Answer 66

C. Intraoperative liver ultrasound

Answer 67

E. Resection, cholecystectomy, and hepaticojejunostomy

Answer 68

D. Internal drainage procedure

Answer 69

E. Analgesia

Answer 70

D. HIDA scan

Answer 71

A. Insertion of a pigtail catheter and cell cytology of drainage

Answer 72

E. All of the above

Answer 73

D. Antibiotic treatment

Answer 74

A. Insulinomas are the most common pancreatic endocrine neoplasm.

Answer 75

A. The gastroduodenal artery (GDA) becomes the superior pancreatidodeuodenal artery as it passes behind the first portion of the duodenum

Answer 76

D. 67-year-old male with 5cm mass in the head of the pancreas, CA 19-9 OF 50 and encasement of the SMA

Answer 77

A. Delayed gastric emptying is common after PPPD and is usually treated surgically.

Answer 78

B. Typical presentation is known as Whipple's triad.

Answer 79

C. Hypoxemia

Answer 80

C. Intraductal papillary neoplasm

Answer 81

A. Duodenotomy and tumor excision with 2-3mm margins

Answer 82

A. ERCP has been considered as the most sensitive radiologic test for the diagnosis.

Answer 83

B. The somatic fibers travel superiorly to the celiac ganglion and interruption of these fibers can stop pain transmission.

Answer 84

``` ADMISSION - Age >55yo - WBC >16,000 - Blood glucose >200mg/dL Serum LDH >350 IU/L Serum AST >250 U/dL ``` INITIAL 48H - Hematrocrit fall >10 points - BUN elevation >5mg/dL - Serum calcium <8 mg/dL - Arterial PO2 <60mmHg - Base deficit >4 mEq/L - Estimated fluid sequestration >6L <3 positive criteria: mild, uncomplicated disease >6 positive criteria: severe disease, 50% mortality

Answer 85

``` ADMISSION Age >70yo WBC >18,000 Blood glucose >220mg/dL Serum LDH >400 IU/L Serum AST >250 U/dL ``` ``` During INITIAL 48H Hematocrit fall >10 points BUN elevation >2mg/dL Serum calcium <8mg/dL Base deficit >5mEq/L Estimated fluid sequestration >4L ``` <3 positive criteria: mild, uncomplicated disease >6 positive criteria: severe disease, 50% mortality

Answer 86

24h of admission - APACHE II score of 8 - CRP >150mg/dL ``` - BISAP BUN >25mg/dL Impaired mental status (GCS <15) SIRS + AGE >60 Pleural effusion + ```

Answer 87

``` Females >50yo ALP>300 ALT>100 Amylase >4000 ```

Answer 88

Nonocclusive mesenteric ischemia

Answer 89

Conservative | Half will resolve spontaneously

Answer 90

Pseudocysts persist because of communication with the main pancreatic duct and/or distal ductal stenosis. EUS-guided internal drainage into stomach or duodenum or transpapillary stenting is the preferred approach. Percutaneous drainage should be avoided because of the risk of external pancreatic fistula.

Answer 91

* History of abdominal pain consistent with acute pancreatitis * >3x elevation of pancreatic enzymes * CT scan if required to confirm diagnosis

Answer 92

* Analgesia * Fluid resuscitation * Predict severity of pancreatitis * Ranson’s criteria * HAPS score * Assess systemic response * SIRS score * SOFA (organ failure)

Answer 93

• Assess response to fluid resuscitation 1) mean arterial pressure 2) heart rate 3) urine output 4) hematocrit • Determine etiology 1) Ultrasound for gallstones/sludge 2) History of alcohol consumption 3) Laboratory evaluation of other causes • MRCP and/or Urgent ERCP if concomitant cholangitis is present 1) not for cholestasis or predicted severe disease per se • Transfer to ICU or specialist center as needed 1) Deterioration or failure to respond to initial management 2) Intensive support for persistent organ failure • Commence enteral nutrition 1) Once normovolemia restored (usually after 6 hours) 2) Commence via NG tube if no gastric stasis • No prophylactic antibiotics or probiotics

Answer 94

• Clinical evaluation 1) Assess cardiovascular, respiratory, and renal function 2) Detect peritonitis and abdominal compartment syndrome * Daily C-reactive protein * Classify severity (mild, moderate, severe, critical) * Detect intolerance of NG EN 1) Advance tube for NJ feeding if needed 2) Consider supplemental parenteral nutrition by day 4

Answer 95

* For significant clinical deterioration and elevated CRP * For suspicion of local pancreatic complications * For suspected bowel ischemia * For acute bleeding (CTa) (if stable enough and consider embolization) * For abdominal compartment syndrome

Answer 96

* For deteriorating patient with suspected infected local complication * “Step up approach” with initial drain guided by current CT scan (percutaneous or endoscopic drainage) * Delay for 3 to 4 weeks with intensive care support, if possible * If failure to respond or secondary deterioration, repeat CT scan, and select appropriate minimally invasive technique based on available expertise and equipment 1) Video-assisted retroperitoneal debridement or percutaneous nephroscopic debridement 2) Endoscopic transluminal debridement 3) Ongoing large bore drainage and irrigation

Answer 97

* Failed “step-up approach” for further debridement/ drainage * Acute abdomen (perforation or ischemia) * Severe abdominal compartment syndrome (rarely)

Answer 98

Diffuse fibrosis Loss of acinar elements Predominant mononuclear cell infiltration

Answer 99

Pancreas divisum is the most common congenital anomaly involving the pancreas, and occurs in up to 10% of children. It is thought to predispose the pancreas to recurrent acute pancreatitis and chronic pancreatitis, due to functional obstruction of a diminutive duct of Santorini that fails to communicate with Wirsung’s duct. Endoscopic stunting through the lesser papilla may result in temporary relief of symptoms, and this response would increase the possibility that a permanent surgical or endoscopic intervention will be successful.

Answer 100

A variant of chronic pancreatitis which is a non-obstructive, diffusely infiltrative disease associated with: 1) fibrosis 2) a mononuclear cell (lymphocyte, plasma cell, or eosinophil) infiltrate, and 3) an increased titer of one or more autoantibodies. It is associated with illnesses with suspected or proven autoimmune etiology, such as Sjögren’s syndrome, rheumatoid arthritis, and type I DM. AIP has two types: I: Accompanying systemic or multiorgan dysfunction II: Restricted to the pancreas Compressive stenosis of the intrapancreatic portion of the common bile duct is frequently seen in both types of AIP, along with symptoms of obstructive jaundice. Increased levels of serum β-globulin or immunoglobulin G4 are also present. Steroid therapy is uniformly successful in ameliorating the disease, including any associated bile duct compression. 136 CFTR mutations that result in dislocation of the transmembrane protein have been found in AIP, and steroid therapy results in a normalization of the CFTR localization and a resumption of normal chloride and bicarbonate secretion.

Answer 101

Induration Nodular scarring Lobular regions of fibrosis As the disease progresses, there is a loss of normal lobulation, with thicker sheets of fibrosis surrounding a reduced acinar cell mass and dilatation of ductular structures. In severe chronic pancreatitis, there is considerable replacement of acinar tissue by broad, coalescing areas of fibrosis, and the islet size and number are reduced. Small arteries appear thickened, and neural trunks become prominent.

Answer 102

Calcium carbonate crystals trapped in a matrix of fibrillar and other material. The fibrillar center of most stones contains no calcium but rather a mixture of other metals. This suggests that stones form from an initial non calcified protein precipitate, which serves as a focus for layered calcium carbonate precipitation.

Answer 103

Fluid: Acute pancreatic fluid collection (APFC) Infected APFC Solid with fluid: Acute necrotic collection (ANC) Infected ANC

Answer 104

Fluid: Pseudocyst Infected pseudocyst Solid with fluid: Walled off necrosis (WON)

Answer 105

(a) diagnosis, (b) the evaluation of severity of disease, (c) detection of complications, and (d) assistance in determining treatment options. Transabdominal ultrasonography is frequently used as a screening method for patients with abdominal symptoms or trauma, and the extension of ultrasonic imaging to include endoscopic ultrasound (EUS) and laparoscopic US have resulted in the highest-resolution images that are capable of detecting very small (<1 cm) abnormalities in the pancreas. EUS is now frequently used as a preliminary step in the evaluation of patients with pancreatic disease, and magnetic resonance cholangiopancreatography (MRCP) is increasingly being used to select patients who are candidates for the most invasive imaging method, ERCP

Answer 106

Ultrasonography is frequently used as an initial imaging method in patients with abdominal symptoms, and changes consistent with pancreatic duct dilatation, intraductal filling defects, cystic changes, and a heterogeneous texture are seen in chronic pancreatitis (Fig. 33-26). The sensitivity of transabdominal ultrasonography ranges from 48% to 96%, and it is operator dependent. However, the contour, texture, and ductal pattern are usually quite discernible, and it is a reliable method for periodic reexamination to determine the efficacy of treatment. Although it is more operator dependent than transabdominal ultrasonography, EUS provides not only imaging capability but also adds the capacity to obtain cytologic and chemical samples of tissue and fluid aspirated with linear array monitoring.

Answer 107

CT scanning has affected the diagnosis of pancreatic disease more broadly than any other method. Duct dilatation, calculous disease, cystic changes, inflammatory events, and anomalies are all detectable with a resolution of 3 to 4 mm (Fig. 33-28). CT scanning has a false-negative rate of <10% for chronic pancreatitis, but early or mild chronic disease may go undetected by CT imaging. The earliest changes are dilatation of secondary ducts and heterogeneous parenchymal changes, which are detectable by EUS and ERCP. Another drawback of CT scanning is its lower sensitivity for detecting small neoplasms, which are seen with increased frequency in chronic pancreatitis and may be invisible to all modalities except EUS.

Answer 108

DUCTAL CHANGES Duct size>3mm (ductal dilatation) Tortuous pancreatic duct (duct irregularity) Intraductal echogenic foci (stones or calcification) Echogenic duct wall (ductal fibrosis) Side-branch ectasia (periductal fibrosis) PARENCHYMAL CHANGES Inhomogenous echopattern (edema) Reduced echogenic foci (1-3mm) (edema) Enhanced echogenic foci (calcifications) Prominent inter lobular septae (fibrosis) Lobular outer gland margin (fibrosis, glandular atrophy) Large echo-poor cavities (>5mm) (pseudocyst)

Answer 109

The resolution of cross-sectional MRI scanning is now approaching that of CT scanning, although the availability of MRI scanners and the complexity of the images produced have limited their large-scale use for routine imaging of the pancreas. MRCP has been shown to be an effective screening technique for disclosing ductal abnormalities that correlates closely with the contrast-filled ducts imaged by ERCP. The advantages of MRCP include its noninvasive methodology and its ability to image obstructed ducts that are not opacified by ERCP injection. It is therefore a useful screening study to detect duct abnormalities and to confirm the need for interventional procedures. Oral, IV, and intraductal contrast are unnecessary for MRCP, and its lack of ionizing radiation makes this the safest method to image the ductal system in high-risk patients.

Answer 110

For the diagnosis and staging of chronic pancreatitis, ERCP is considered to be the gold standard. It also serves as a vehicle that enables other diagnostic and therapeutic maneuvers, such as biopsy or brushing for cytology, or the use of stents to relieve obstruction or drain a pseudocyst (Fig. 33-30). Unfortunately, ERCP also carries a risk of procedure-induced pancreatitis that occurs in approximately 5% of patients. Patients at increased risk include those with sphincter of Oddi dysfunction and those with a previous history of post-ERCP pancreatitis. Post-ERCP pancreatitis occurs after uncomplicated procedures, as well as after those that require prolonged manipulation. Severe pancreatitis and deaths have occurred after ERCP. It should be reserved for patients in whom the diagnosis is unclear despite the use of other imaging methods, or in whom a diagnostic or therapeutic maneuver is specifically indicated.

Answer 111

(a) reducing secretion and/or decompress the secretory compartment, (b) resecting the focus of chronic inflammatory change, or (c) interrupting the transmission of afferent neural impulses through neural ablative procedures.

Answer 112

A collection of enzyme-rich pancreatic juice that occurs early in the course of acute pancreatitis, or that forms after a pancreatic duct leak; located in or near the pancreas; it lacks a well-organized wall of granulation or fibrous tissue

Answer 113

A focal or diffuse area of nonviable pancreatic parenchyma, typically occupying >30% of the gland and containing liquefied debris and fluid

Answer 114

An organized collection of sterile necrotic debris and fluid with a well-defined margin or wall within the normal domain of the pancreas

Answer 115

A collection of pancreatic juice enclosed within a perimeter of early granulation tissue, usually as a consequence of acute pancreatitis that has occurred within the preceding 3–4 wk

Answer 116

A collection of pancreatic fluid surrounded by a wall of normal granulation and fibrous tissue, usually persisting for >6 wk

Answer 117

Any of the above in which gross purulence (pus) is present, with bacterial or fungal organisms documented to be present

Answer 118

The triad consists of symptomatic fasting hypoglycemia, a documented serum glucose level <50 mg/dL, and relief of symptoms with the administration of glucose. Manifested in a patient with insulinoma, the most common functional pancreatic endocrine neoplasm.

Answer 119

Answer: C In 15 to 20% of patients, the right hepatic artery will arise from the superior mesenteric artery and travel upward toward the liver along the posterior aspect of the head of the pancreas (referred to as a replaced right hepatic artery). It is important to look for this variation on preoperative computed tomographic (CT) scans and in the operating room (OR) so the replaced hepatic artery is recognized and injury is avoided. (See Schwartz 10th ed., p. 1345.)

Answer 120

Answer: A A chronic collection of pancreatic fluid surrounded by a non-epithelialized wall of granulation tissue and fibrosis is referred to as a pseudocyst. Pseudocysts occur in up to 10% of patients with acute pancreatitis, and in 20 to 38% of patients with chronic pancreatitis, and thus, they comprise the most common complication of chronic pancreatitis. (See Schwartz10th ed., pp. 1375–1376.)

Answer 121

Answer: B Approximately 90% of insulinomas are sporadic, and 10% are associated with the multiple endocrine neoplasia (MEN)1 syndrome. Insulinomas associated with the MEN1 syndrome are more likely to be multifocal and have a higher rate of recurrence. (SeeSchwartz10thed.,p.1391.)

Answer 122

Answer: D See Figure 33-1. (See Schwartz 10th ed., Figure 33-75, p. 1409.) Detailed clinical history and pancreas protocol CT - -> Symptomatic, or MCN/IPMN >3cm? - -----> Resect. --> Asymptomatic MCN/IPMN <3 cm, serous cystadenoma, branch duct IPMN ------> Further evaluation. FURTHER EVALUATION 1) <1cm - Repeat CT in 1 year. Repeat CT: - <1cm: Repeat CT in 1 year. - ≤2 cm: Repeat CT q 6–12 months ``` - 2-3cm: EUS -FNA MRCP/ERCP • Mucin present • CEA >200 ng/mL • Atypical cells present • Solid component • Dilated main pancreatic duct? ---> if yes, resect. --> If none, repeat CT q 3–6 months . ``` ``` 2) 1-3cm EUS -FNA MRCP/ERCP • Mucin present • CEA >200 ng/mL • Atypical cells present • Solid component • Dilated main pancreatic duct? ---> if yes, resect. --> If none, repeat CT q 3–6 months. ```

Answer 123

Answer: A See table 33-1. (See Schwartz 10th ed, able 33-7, p. 1356.)

Answer 124

Answer: A Because somatostatin inhibits pancreatic and biliary secretions, patients with a somatostatinoma present with gallstones due to bile stasis, diabetes due to inhibition of insulin secretion, and steatorrhea due to inhibition of pancreatic exocrine secretion and bile secretion. Most somatostatinomas originate in the proximal pancreas or the pancreatoduodenal groove, with the ampulla and periampullary area as the most common site (60%). The most common presentations are abdominal pain (25%), jaundice (25%), and cholelithiasis (19%). This rare type of pancreatic endocrine tumor is diagnosed by confirming elevated serum somatostatin levels, which are usually above 10 ng/mL. Although most reported cases of somatostatinoma involve metastatic disease, an attempt at complete excision of the tumor and cholecystectomy is warranted in fit patients. (SeeSchwartz10thed.,p.1393.)

Answer 125

Answer: D This type is the largest subgroup in the classification scheme proposed by Singer and Chari, and includes patients with calcific pancreatitis of most etiologies (Table 33-2). Although the majority of patients with calcific pancreatitis have a history of alcohol abuse, stone formation and parenchymal calcification can develop in a variety of etiologic subgroups; hereditary pancreatitis and tropical pancreatitis are particularly noteworthy for the formation of stone disease. The clinician should therefore avoid the assumption that calcific pancreatitis confirms the diagnosis of alcohol abuse. (See Schwartz 10th ed., able 33-11, p. 1365.)

Answer 126

Answer: C Endoscopic retrograde cholangiopancreatography (ERCP) is considered to be the gold standard or the diagnosis and staging of chronic pancreatitis. It also serves as a vehicle that enables other diagnostic and therapeutic maneuvers, such as biopsy or brushing or cytology, or the use of stents to relieve obstruction or drain a pseudocyst (Fig. 33-2). Unfortunately, ERCP also carries a risk of procedure-induced pancreatitis that occurs in approximately 5% of patients. Patients at increased risk include those with sphincter of Oddi dysfunction and those with a previous history of post-ERCP pancreatitis. Post-ERCP pancreatitis occurs after uncomplicated procedures, as well as after those that require prolonged manipulation. Severe pancreatitis and deaths have occurred after ERCP, it should be reserved for patients in whom the diagnosis is unclear despite the use of other imaging methods, or in whom a diagnostic or therapeutic maneuver is specifically indicated. (See Schwartz 10th ed., Figure 33-29, pp. 1370–1371.)

Answer 127

Answer: B Fifty percent of gastrinomas metastasize to lymph nodes or the liver, and are therefore considered malignant. Patients who meet criteria for operability should undergo exploration for possible removal of the tumor. Although the tumors are submucosal, a full-thickness excision of the duodenal wall is performed if a duodenal gastrinoma is found. All lymph nodes in Passaro triangle are excised for pathologic analysis. If the gastrinoma is found in the pancreas and does not involve the main pancreatic duct, it is enucleated. Pancreatic resection is justified for solitary gastrinomas with no metastases. A highly selective vagotomy can be performed if unresectable disease is identified or if the gastrinoma cannot be localized. This may reduce the amount of expensive proton pump inhibitors required. In cases in which hepatic metastases are identified, resection is justified if the primary gastrinoma is controlled and the metastases can be safely and completely removed. Debulking or incomplete removal of multiple hepatic metastases is probably not helpful, especially in the setting of MEN1. The application of new modalities such as radiofrequency ablation seems reasonable, but data to support this approach are limited. Postoperatively, patients are followed with fasting serum gastrin levels, secretin stimulation tests, octreotide scans, and CT scans. In patients found to have inoperable disease, chemotherapy with streptozocin, doxorubicin, and 5-fluorouracil (5-FU) is used. Other approaches such as somatostatin analogues, interferon, and chemoembolization also have been used in gastrinoma with some success. (See Schwartz 10th ed., p. 1392.)

Answer 128

Answer: A Intraductal papillary mucinous neoplasms (IPMNs) usually occur within the head of the pancreas and arise within the pancreatic ducts. The ductal epithelium forms a papillary projection into the duct, and mucin production causes intraluminal cystic dilation of the pancreatic ducts (Fig. 33-3). Imaging studies demonstrate diffuse dilation of the pancreatic duct, and the pancreatic parenchyma is often atrophic due to chronic duct obstruction. However, classic features of chronic pancreatitis, such as calcification and a beaded appearance of the duct, are not present. At ERCP, mucin can be seen extruding from the ampulla of Vater, also called fish-eye lesion, that is virtually diagnostic of IPMN (Fig.33-4). (See Schwartz 10th ed., Figures 33-77 and 33-8, pp. 1411–1412.)

Answer 129

Answer: D Pain from chronic pancreatitis has been ascribed to three possible etiologies. Ductal hypertension, due to strictures or stones, may predispose to pain that is initiated or exacerbated by eating. Chronic pain without exacerbation may be related to parenchymal disease or retroperitoneal inflammation with persistent neural involvement. Acute exacerbations of pain in the setting of chronic pain may be due to acute increases in duct pressure or recurrent episodes of acute inflammation in the setting of chronic parenchymal disease. Nealon and Matin have described these various pain syndromes as being predictive of the response to various surgical procedures. Pain that is found in association with ductal hypertension is most readily relieved by pancreatic duct decompression, through endoscopic stenting or surgical decompression. (See Schwartz 10th ed., p. 1371.)

Answer 130

Answer: C The surgical relief of pain due to obstructive pancreatopathy may be dependent on the degree of underlying fibrosis rather than the presence of ductal obstruction, per se, according to a recent study from Johns Hopkins by Cooper et al. Thirty-five patients with chronic pain associated with evidence of duct obstruction were treated with local resection of the pancreatic head and longitudinal pancreatico-jejunostomy (LR-LPJ), or Frey procedure, and the degree of pain resolution after surgery was compared to the degree of underlying parenchymal fibrosis. After a follow-up that averaged 22 months, patients with more than 80% fibrosis had 100% pain relief, whereas only 60% patients with less than 10% fibrosis experienced substantial or complete pain relief (Fig. 33-5). These findings suggest that minimal fibrosis, or “minimal change chronic pancreatitis,” may produce chronic pain due to extrapancreatic or “peri-pancreatic” inflammatory events which are not ameliorated by decompression. (See Schwartz 10th ed., Figure 33-31, pp. 1371–1372.)

Answer 131

Answer: A The traditional approach to surgical treatment of chronic pancreatitis and its complications has maintained that surgery should be considered only when the medical therapy of symptoms has ailed. Nealon and Thompson published a landmark study in 1993, however, that showed that the progression of chronic obstructive pancreatitis could be delayed or prevented by pancreatic duct decompression. No other therapy has been shown to prevent the progression of chronic pancreatitis, and this study demonstrated the role of surgery in the early management of the disease (Table 33-3). Small-duct disease or “minimal change chronic pancreatitis” are causes or uncertainty over the choice of operation, however. Major resections have a high complication rate, both early and late, in chronic alcoholic pancreatitis, and lesser procedures often result in symptomatic recurrence. So the choice of operation and the timing of surgery are based on each patient’s pancreatic anatomy, the likelihood (or lack thereof) that further medical and endoscopic therapy will halt the symptoms of the disease, and the chance that a good result will be obtained with the lowest risk of morbidity and mortality. Finally, preparation for surgery should include restoration of protein-caloric homeostasis, abstinence from alcohol and tobacco, and a detailed review of the risks and likely outcomes to establish a bond of trust and commitment between the patient and the surgeon. (See Schwartz 10th ed., able 33-20, p. 1382.)

Answer 132

Answer: A The common element of these variations on the theme of LR-LPJ remains the excavation or “coring out” of the central portion of the pancreatic head. It remains uncertain, however, whether and to what degree the dichotomy needs to be extended into the body and tail. The logical conclusion of all of these efforts is that the head of the pancreas is the nidus of the chronic inflammatory process in chronic pancreatitis, and that removal of the central portion of the head of the gland is the key to the successful resolution of pain long-term. (See Schwartz 10th ed., pp. 1342 and 1387.)

Answer 133

Answer: D The preservation of the pylorus has several theoretical advantages, including prevention of reflux of pancreaticobiliary secretions into the stomach, decreased incidence of marginal ulceration, normal gastric acid secretion and hormone release, and improved gastric function. Patients with pylorus- preserving resections have appeared to regain weight better than historic controls in some studies. Return of gastric emptying in the immediate postoperative period may take longer after the pylorus-preserving operation, and it is controversial whether there is any significant improvement in long-term quality of life with pyloric preservation. Techniques for the pancreaticojejunostomy include end- to-side or end-to-end and duct-to-mucosa sutures or invagination (Fig. 33-6). Pancreaticogastrostomy has also been investigated. Some surgeons use stents, glue to seal the anastomosis, or octreotide to decrease pancreatic secretions. No matter what combination of these techniques is used, the pancreatic leakage rate is always about 10%. Therefore, the choice of techniques depends more on the surgeon’s personal experience. (See Schwartz 10th ed., Figure 33-73, p. 1403.)

Answer 134

Answer: C Fifty percent of gastrinomas metastasize to lymph nodes for the liver, and are therefore considered malignant. Patients who meet criteria for operability should undergo exploration for possible removal of the tumor. Although the tumors are submucosal, a full-thickness excision of the duodenal wall is performed if a duodenal gastrinoma is found. All lymph nodes in Passaro triangle are excised for pathologic analysis. If the gastrinoma is found in the pancreas and does not involve the main pancreatic duct, it is enucleated. Pancreatic resection is justified for solitary gastrinomas with no metastases. A highly selective vagotomy can be performed if unresectable disease is identified or if the gastrinoma cannot be localized. This may reduce the amount of expensive proton pump inhibitors required. In cases in which hepatic metastases are identified, resection is justified if the primary gastrinoma is controlled and the metastases can be safely and completely removed. Debulking or incomplete removal of multiple hepatic metastases is probably not helpful, especially in the setting of MEN1. The application of new modalities such as radiofrequency ablation seems reasonable, but data to support this approach are limited. Postoperatively, patients are followed with fasting serum gastrin levels, secretin stimulation tests, octreotide scans, and CT scans. In patients found to have inoperable disease, chemotherapy with streptozocin, doxorubicin, and 5-fluorouracil (5-FU) is used. Other approaches such as somatostatin analogues, interferon, and chemoembolization also have been used in gastrinoma with some success. Unfortunately, a biochemical cure is achieved in only about one-third of the patients operated on for Zollinger-Ellison syndrome (ZES). Despite the lack of success, long-term survival rates are good, even in patients with liver metastases. The 15-year survival rates for patients without liver metastases is about 80%, while the 5-year survival rate for patients with liver metastases is 20 to 50%. Pancreatic tumors are usually larger than tumors arising in the duodenum, and more often have lymph node metastases. In gastrinomas, liver metastases decrease survival rates, but lymph node metastases do not. The best results are seen after complete excision of small sporadic tumors originating in the duodenum. Large tumors associated with liver metastases, located outside of Passaro triangle, have the worst prognosis. (See Schwartz 10th ed., p. 1392.)

Answer 135

ANSWER: B COMMENTS: This ERCP study shows the classic “double-duct sign:” dilation of the biliary system above an area of abrupt narrowing and abrupt termination of the main pancreatic duct. These findings place the primary abnormality in the geographic location of the pancreatic head, and it is not uncommon for a pancreatic neoplasm to involve both ducts. Chronic pancreatitis may cause biliary obstruction, but the obstruction in the biliary systems is usually more distal. Likewise, there are no coexistent changes in this patient, such as irregular beading of the pancreatic duct, to suggest that chronic pancreatitis is present. Cholangiocarcinoma may be responsible for the stenosis in the biliary system, but cholangiocarcinomas rarely become large enough to involve the pancreatic duct. With pancreas divisum, injection of the major papilla opacifies only a short, tapering ventral duct draining the caudal portion of the pancreatic head and uncinate process. Injection of the minor papilla demonstrates the dorsal duct draining the major portion of the gland.

Answer 136

ANSWER: B COMMENTS: Insulinomas are usually single and benign and are rarely ectopic. Localization of an insulinoma can be difficult, and preoperative imaging along with thorough mobilization and exploration of the pancreas is mandatory. Intraoperative ultrasonography is indispensable. For localized lesions, simple enucleation is the pre- ferred treatment, but the integrity of the pancreatic duct must be ascertained. If the lesion cannot be identified and the biochemical basis of the diagnosis is firm, blind distal pancreatic resection with a careful histologic examination of the specimen may be necessary. Intraoperative monitoring of serum glucose levels has also been used. Diazoxide inhibits insulin release from beta cells and is occasionally used for preoperative control or for patients with recurrent postoperative hypoglycemia. For patients with metastatic malignant insulinoma, tumor debulking may be beneficial, as is the use of streptozocin and 5-fluorouracil. Gastrinoma, not insulinoma, is the most common pancreatic adenoma associated with multiple endocrine adenomatosis type I syndrome. Parathyroid disease should be excluded or treated before surgical intervention for gastrinoma.

Answer 137

ANSWER: D COMMENTS: Zollinger-Ellison syndrome is caused by a gastrin- producing islet cell tumor. Verner-Morrison syndrome is caused by an islet cell tumor that produces vasoactive intestinal peptide. Zollinger- Ellison syndrome is associated with a marked increase in gastric acid secretion and with diarrhea. Hypercalcemia may occur because of associated parathyroid abnormalities. Verner-Morrison syndrome is characterized by watery diarrhea, hypokalemia, and achlorhydria. Hypercalcemia may occur, but the parathyroids are usually normal. Both syndromes are frequently the result of malignant islet cell tumors.

Answer 138

ANSWER: C COMMENTS: Patients with glucagon-secreting tumors have diabetes, anemia, weight loss, venous thrombosis, glossitis, and a characteristic cutaneous lesion known as necrolytic migratory erythema. The lesion is rare and often metastatic at the time of diagnosis. Treatment is directed at achieving as complete a resection as possible. Postoperatively, chemotherapy with dacarbazine or streptozocin may be useful for a residual or recurrent disease.

Answer 139

ANSWER: B COMMENTS: Pancreatic contusions or lacerations without ductal disruption are managed by drainage alone. The pancreatic neck is a frequent site of pancreatic injury when it occurs with blunt trauma. Distal pancreatectomy with identification and closure of the proximal duct and drainage is safe, and resections involving up to 80% of an otherwise normal gland can be accomplished without subsequent endocrine insufficiency. In theory, Roux-en-Y pancreaticojejunostomy may be desirable to preserve pancreatic tissue, but it is not recommended for the management of acute injuries because of the risk associated with a pancreatic anastomosis and the need to open the gut. Pancreaticoduodenectomy is indicated for patients with severe combined duodenal, pancreatic, and bile duct injuries. Most pancreatic injuries are the result of penetrating trauma, although the gland is vulnerable to blunt trauma because of its fixed position anteriorly over the vertebral column. The presence of significant pancreatic injury following blunt trauma is often not initially apparent. Hyperamylasemia in serum or peritoneal fluid suggests the diagnosis, but a negative peritoneal tap or lavage does not exclude retroperitoneal injury. Retroperitoneal hematomas in the upper part of the abdomen should be explored to exclude pancreatic ductal injury. Pancreatitis is the most common cause of pseudocyst, although about 25% occur as a result of trauma.

Answer 140

ANSWER: E COMMENTS: Ethanol is the prevalent etiologic factor in acute pancreatitis. There are several contributory mechanisms by which alcohol-induced pancreatic injury occurs. Ethanol causes pancreatic ductal hypertension by increasing ampullary resistance and by intraductal deposition of stone proteins. Concomitantly, ethanol stimulates gastric acid secretion and increases pancreatic exocrine secretion via the release of secretin. The combination of ductal obstruction with stimulated secretion may result in enzyme extravasation. Acetaldehyde, the metabolic product of ethanol, injures acinar cells by increasing membrane permeability and disrupting the microtubule structure. The elevated levels of serum triglycerides induced by alcohol are a source of cytotoxic free fatty acids. Alcohol also impairs normal trypsin inhibition and reduces pancreatic blood flow. All of these effects may contribute to intraglandular enzyme activation and the development of acute alcoholic pancreatitis.

Answer 141

ANSWER: E COMMENTS: In the Western world, alcohol use accounts for about 75% of cases of chronic pancreatitis. Approximately 20% of cases are considered idiopathic. In parts of Africa and Asia, protein malnutrition is an important etiologic factor. Other, less common causes of chronic pancreatitis include pancreatic duct obstruction (secondary to stenosis or pancreas divisum), hyperparathyroidism, trauma, cystic fibrosis (CF), and hereditary causes. Unlike acute pancreatitis, calculous biliary disease is not a typical cause of chronic pancreatitis. Certain infections (particularly viral) and drugs are among the many factors that can produce acute, rather than chronic, pancreatitis.

Answer 142

ANSWER: D COMMENTS: A heterotopic pancreas is a pancreatic tissue located at sites other than the normal location of the gland. Ectopic pancreatic tissue has been described at many anatomic locations but is typically found in the stomach, the duodenum, or a Meckel’s diverticulum. Theories of origin include metaplasia (the favored theory) and transplantation. Histologic findings range from those of a rudimentary structure to a fully formed gland. Most heterotopic rests contain ducts, and both endocrine and exocrine elements may be present. This entity is not uncommon, being described in 1%–2% of autopsies. It is usually asymptomatic. When symptoms occur, they are related to the location of the ectopic site and include obstruction (as a result of intussusception), ulceration, and bleeding. Although malignancy has been reported, there is no evidence that heterotopic pancreatic tissue is predisposed to cancer. The typical gross appearance is a submucosal nodule, often with central umbilication. Resection is indicated for symptomatic lesions and is appropriate diagnostically for incidental lesions discovered during operations for other reasons.

Answer 143

ANSWER: C COMMENTS: An annular pancreas is a congenital anomaly involving a band of pancreatic tissue encircling the second portion of the duodenum. The annular tissue appears to originate from the embryologic ventral pancreas. Causal theories include abnormal fixation of the ventral pancreatic primordium before gut rotation, failure of involution of part of the ventral pancreas, and the development of heterotopic pancreatic tissue in the duodenum. Approximately one-half of these cases are diagnosed in infants and the remainder in adults, with a peak during the fourth decade of life. Most patients are asymptomatic. Clinical findings are obstruction in infants and children and obstruction, ulceration, or pancreatitis in adults. Associated anomalies include duodenal stenosis or atresia and Down syndrome. Treatment of symptomatic patients consists of surgical bypass by duodenoduodenostomy or duodenojejunostomy. Gastrojejunostomy can also alleviate obstruction but risks marginal ulceration. Resection or division of the annular band is not advised because it risks the development of a pancreatic fistula and may fail to relieve the obstruction.

Answer 144

ANSWER: B COMMENTS: The pancreas is formed from two outpouchings of the primitive gut. The dorsal pancreas originates from the duodenum, and the ventral pancreas begins as a bud from the hepatic diverticulum, which itself is an outpouching of the duodenum. Other outgrowths from the hepatic diverticulum mature into the liver, gallbladder, and bile ducts. During normal fetal development, the ventral pancreas rotates along with the primitive gut and fuses with the dorsal component. The ventral pancreas constitutes the uncinate process and the inferior portion of the head of the gland in the fully developed state, and the dorsal pancreas forms the remainder of the gland. Abnormalities in this developmental process result in recognized congenital anomalies that can be clinically important. An understanding of this embryologic development is also important for recognizing the relationship of the pancreas to adjacent vascular structures during pancreatic operations.

Answer 145

ANSWER: C COMMENTS: Epidemiologic studies have identified various demographic, medical, environmental, and dietary factors that have some relationship to pancreatic cancer. The most firmly established risk factor is cigarette smoking. Experimentally, nitrosamines have been found to be carcinogenic. In addition, the carcinogens in cigarettes have been related to K-ras oncogene mutations, which are frequent in pancreatic cancer. Alcohol has not been demonstrated conclusively to be a risk factor independent of cigarettes. The previously reported association of pancreatic cancer with coffee consumption is questionable. Diets high in fats and meat may be associated with pancreatic cancer, whereas diets high in fruits and vegetables may be protective. Certain occupational and industrial exposures have an increased risk. There may be some association with diabetes mellitus and certain forms of chronic pancreatitis, but the relationship is not considered causal. Previous gastrectomy has been associated with increased risk, whereas tonsillectomy has been observed to be protective.

Answer 146

ANSWER: D COMMENTS: Several systems have been devised to gauge the severity of acute pancreatitis. These systems involve multiple clinical, biochemical, and, sometimes, radiologic criteria. The most widely used system in the United States, developed by Ranson, was based on retrospective analysis and subsequent prospective verification. The Ranson criteria include 11 parameters determined at the time of admission or during the subsequent 48 h. Patients with three or more criteria have more severe disease and are at increased risk for septic complications and death. The criteria reflect the patient’s underlying status, the severity of the retroperitoneal inflammatory process, and the effects on renal and respiratory function. The Ranson criteria were originally developed for alcoholic pancreatitis and have been modified somewhat for gallstone pancreatitis. For example, a rise in the serum BUN level of more than 2 mg/dL is 1 of the 10 criteria for gallstone pancreatitis, but the rise must be more than 5 mg/dL to meet the criteria for alcoholic pancreatitis (a subtle point). ``` The criteria include the following at admission: age > 55 years, WBC > 16 cells per MCL, blood glucose > 200 mg/dL, AST > 250 IU/L, and LDH > 350 IU/L. ``` ``` At 48 h from admission, the additional criteria include the following: calcium < 8 mg/dL, hematocrit fall > 10%, hypoxemia (pO2 < 60 mmHg), BUN increased by 5 mg/dL or more, base deficit > 4, and sequestration of fluid > 6 L. ``` A score of 0 to 2 assigns a 2% mortality, 3 to 4: 15%, 5 to 6: 40%, and greater than 7: 100%. Other physiologic scoring systems, such as the Acute Physiology, Age, and Chronic Health Evaluation II, are also useful prognostically, although they are not designed specifically for acute pancreatitis.

Answer 147

ANSWER: E COMMENTS: The diagnosis of acute pancreatitis is based on signs and symptoms, supported by biochemical findings and morphologic abnormalities seen on imaging studies such as CT. No biochemical feature is pathognomonic of acute pancreatitis. Hyperamylasemia, hyperlipasemia, and elevations in urinary amylase levels and the ACCR are typical of acute pancreatitis but are not specific or sensitive, and they can occur with other abdominal and extraabdominal disorders. Hypocalcemia may occur as a consequence of pancreatitis, but it is also nonspecific. There is no absolute level of serum amylase or lipase that is diagnostic of acute pancreatitis. Marked elevations are more indicative of pancreatitis but are not themselves diagnostic. Both amylase and lipase levels may be elevated in a number of conditions that can be confused with acute pancreatitis, such as acute cholecystitis, perforated peptic ulcer, and intestinal infarction. Moreover, severe pancreatitis can occur without substantial elevations in these serum enzymes. Elevations in serum and urinary amylase levels and in the ACCR, as determined by the following equation, are typical of acute pancreatitis. ACCR = Uamy/Samy × Scr/Ucr ×100 where U = urine, S = serum, amy = amylase, and cr = creatinine. Elevation of the ACCR above the normal 2%–5% range is not specific for pancreatitis, but a normal ratio in the presence of hyperamylasemia suggests that the hyperamylasemia is the result of something other than pancreatitis. Serum and urinary amylase levels and the ACCR may be normal in patients with chronic pancreatitis or elevated during an acute exacerbation. Renal disease may be associated with low urinary amylase levels and an elevated ACCR. Common duct stones may produce hyperamylasemia without true pancreatitis. The urinary amylase level is elevated, although the ACCR may be normal. With macroamylasemia, amylase forms complexes with serum proteins too large for glomerular filtration. The serum amylase level is therefore elevated, but urinary amylase levels and the ACCR are low. The diagnosis can be confirmed by electrophoresis. Abdominal pain has been reported in more than one-half of patients with macroamylasemia, although the biochemical abnormality is probably not etiologically related to the pain. Hyperamylasemia predominantly caused by salivary amylase may also be associated with a low urinary amylase level and ACCR because compared with the pancreatic isoenzyme, the salivary isoenzyme is cleared more slowly by the kidneys.

Answer 148

ANSWER: D COMMENTS: Most patients with pancreatic cancer do not have resectable disease. Palliative treatment is directed to relieve obstruction of the bile duct and duodenum and to alleviate pain. For lesions demonstrated to be unresectable before laparotomy, nonoperative relief of biliary obstruction can be achieved by the endoscopic (preferred) or transhepatic route. Surgical bypass generally provides more durable relief with less need for further intervention. It is preferred for patients when unresectability is determined at the time of laparotomy. Pancreatic cancers can obstruct the duodenum or the proximal jejunum near the ligament of Treitz. Traditionally, many surgeons have favored routine “double bypass” (biliary and duodenal) for operated patients because the rate of duodenal obstruction that develops later in patients treated by biliary bypass alone has been cited to be 5%–30%. However, duodenal obstruction does not develop in most patients, and gastrojejunostomy is sometimes associated with problems such as bleeding or delayed gastric emptying. The selective approach is therefore appropriate. Patients with obstructive symptoms or impending obstruction as a result of tumor location should undergo gastrojejunostomy. Gastrojejunostomy is also advisable for patients with an anticipated longer survival, such as those whose lesions are not resected because of local tumor invasion but because of hepatic or peritoneal metastases. Endoscopic placement of a duodenal stent is another option, but the results are not always satisfactory. Additionally, choledochojejunostomy, cholecystojejunostomy, hepaticojejunostomy, and choledochoduodenostomy are each appropriate for the management of distal bile duct obstruction. A Roux-en-Y configuration is preferred by many surgeons for choledochojejunostomy reconstruction, although a simple loop (with or without distal enteroenterostomy) also suffices. Cholecystojejunostomy is relatively simple but should be avoided if the gallbladder is diseased or when cystic duct patency cannot be demonstrated or may be jeopardized by tumor proximity. It is sometimes taught that choledochoduodenostomy should be avoided with malignant obstruction because of possible tumor growth and eventual reobstruction. In reality, choledochoduodenostomy can be an effective solution provided that the common bile duct is sufficiently dilated and the duodenum is pliable and unobstructed.

Answer 149

ANSWER: C COMMENTS: Cystadenoma and cystadenocarcinoma are cystic neoplasms of the pancreas that are most commonly manifested as mass lesions in middle-aged women. Serous and mucinous types are recognized, and the risk for malignancy is significant with the mucinous variety. Cystadenoma is more common than its malignant counterpart, but malignant transformation may occur. EUS with sampling for cytology, mucin, and carcinoembryonic antigen can be useful for gauging the likelihood of cancer. Without resection, however, exclusion of malignancy can be difficult. Internal drainage of cystic neoplasms is not an appropriate therapy. Complete excision should be carried out whenever possible. The 5-year survival rate after resection of cystadenocarcinoma is approximately 50%. Occasionally, islet cell tumors, ductal adenocarcinomas, or other unusual tumors (e.g., papillary and cystic pancreatic neoplasms) have cystic components.

Answer 150

ANSWER: B COMMENTS: The pancreas can be divided into various parts: head, uncinate, neck, body, and tail. The uncinate process is the portion of the gland that extends to the left, dorsal to the portal vein and superior mesenteric artery and ventral to the aorta and inferior vena cava. The uncinate process is located caudad and ventral to the left renal vein and cephalad to the distal duodenum. Understanding the extent and location of the uncinate is important during resection of the head of the pancreas. The blood supply of the uncinate is derived from numerous short branches of the superior mesenteric artery and portal vein. When performing pancreatico- duodenectomy, these branches must be carefully controlled to prevent bleeding and avoid injury to the superior mesenteric artery or portal vein.

Answer 151

ANSWER: A COMMENTS: The relationship of the pancreas to neighboring organs and to critical vascular structures is of great surgical significance. The arterial supply to the head of the gland is derived from both the gastroduodenal and the superior mesenteric arteries via the anterior and posterior pancreaticoduodenal arcades. For the most part, the head of the pancreas and the duodenum have a shared blood supply, so they must generally be resected together. However, techniques for “duodenal-sparing” resection of the pancreatic head or “pancreatic-sparing” duodenectomy are appropriate in selected circumstances. The body and tail of the pancreas receive their blood supply mainly from multiple branches of the splenic artery, which also connect with superior mesenteric sources. Variations in major arteries—such as the origin of the right hepatic artery from the superior mesenteric artery and the origin of the middle colic artery from the superior mesenteric artery or dorsal pancreatic artery—place these vessels in close proximity to the head and neck of the pancreas, where they are subject to injury during pancreatectomy. The junction of the splenic vein and superior mesenteric vein to form the portal vein lies behind the neck of the pancreas. Usually, these vessels do not have large anterior tributaries in this area, but appropriate caution must nonetheless be exercised when developing this plane during pancreatic operations.

Answer 152

ANSWER: A COMMENTS: When the clinical situation suggests a resectable pancreatic neoplasm in a good-risk patient with biliary obstruction, surgery for potential resection is generally indicated without additional tests. Routine preoperative biliary decompression is not advantageous in this setting because it does not improve operative outcomes and may increase the morbidity associated with resection. Endoscopic biliary decompression is invaluable, of course, for palliation of obstruction in patients deemed inoperable or if operation is to be delayed. CT or MRI is usually adequate in assessing the extent of disease and resectability preoperatively. EUS is extremely useful for identifying small tumors that are inapparent on CT, for obtaining cytologic material, and somewhat for assessing vascular invasion. Imaging criteria for what constitutes a borderline case vary but would commonly include tumors that abut a substantial (half or greater) circumference of adjacent vessels (hepatic artery, superior mesenteric artery, portal vein) or that narrow the portal-splenic vein confluence. Resection of a pancreatic malignancy offers the only chance for cure. Most commonly, resection of ductal carcinomas involves pancreaticoduodenectomy because most potentially resectable tumors are located in the head or uncinate process of the gland. Tumors originating in the body or tail of the pancreas are often not diagnosed until they are beyond the confines of surgical resection. However, location alone does not contraindicate resection because, stage for stage, tumors in the body have the same survival as tumors in the head of the pancreas. Resection is indicated for physiologically fit patients (age alone is not a contraindication) who do not have metastases beyond the field of resection. Histologic or cytologic confirmation of malignancy can often be obtained intraoperatively but is not necessary before resection if the clinical circumstances suggest cancer and the surgeon is appropriately experienced. For some tumors with local vascular invasion, en bloc resection with reconstruction of the involved vessels is appropriate if a tumor-free resection can be accomplished. Positive lymph nodes outside the resection field, peritoneal metastases, and liver metastases generally contraindicate resection for adenocarcinoma of the exocrine pancreas. However, tumor “debulking” and resection of liver metastases can be beneficial in patients with functioning tumors of the endocrine pancreas.

Answer 153

ANSWER: C COMMENTS: Gross steatorrhea and diarrhea occur when pancreatic exocrine function is reduced to about 10% of normal. Therapy involves limitation of fat intake and administration of adequate amounts of exogenous pancreatic enzyme preparations to provide at least 10% of the normal lipolytic activity in the duodenum at the time when the food substrate is present. Various commercial formulations of pancreatic enzymes are available. Nonencapsulated forms may improve the malabsorption but can be ineffective because of inactivation in the stomach when the pH falls below 4. The addition of H2 blockers may then be useful. Enteric-coated preparations release their enzymes at a pH above 5. Therefore they are useful for patients whose gastric pH remains low to ensure that the enzyme is not released until it reaches the duodenum. The use of encapsulated forms with H2 blockers is counter- productive because the enzyme is released in the stomach and is then inactivated if the pH falls. In addition, enteric-coated preparations are microspheres of varying sizes, and the larger ones do not empty into the duodenum until after the food substrate does.

Answer 154

ANSWER: E COMMENTS: Pancreas divisum currently refers to congenital variations of the pancreatic ducts that result from failed or incomplete fusion of the embryologic ventral and dorsal ductal systems. (Historically, the term may also refer to the rare failure of parenchymal fusion.) There may be complete separation of the ducts, an absent or minimal ventral duct, or only a few meager connections between the systems. As a consequence, most of the pancreatic duct drainage is through the dorsal duct joining the duodenum at the minor papilla. Any existing ventral ducts (Wirsung’s) drain only the uncinate process and the caudal head of the gland rather than the bulk of the gland at the major papilla, as when normally developed. Some variation of pancreas divisum is present in about 10% of the population. In some individuals, it is clinically significant if the relatively stenotic minor papilla imposes an obstruction to ductal flow. This can potentially result in recurrent abdominal pain, acute pancreatitis, or even chronic pancreatitis. The diagnosis is usually made by ERCP, and cannulation of the minor papilla may be required to image the dorsal duct. MRCP might also demonstrate this ductal anatomy. The vast majority (95%) of individuals with pancreas divisum are asymptomatic.

Answer 155

ANSWER: D COMMENTS: The centroacinar cells secrete a bicarbonate-rich solution by an active transport mechanism, primarily in response to secretin. Cholecystokinin is the primary stimulant of enzyme secretion from the acinar cells. The bicarbonate and chloride contents of pancreatic juice are reciprocally related. As ductal flow rates increase, the bicarbonate concentration increases and the chloride concentration decreases. This is the result of two processes: (1) changes in passive exchange of intraductal bicarbonate for intracellular chloride and (2) changes in the relative contribution of acinar cell secretion. Acinar cells secrete fluid high in chloride in addition to digestive enzymes. In contradistinction to anion concentrations, the concentrations of sodium and potassium in pancreatic duct secretions remain relatively constant despite the flow rate and are similar to their concentrations in plasma.

Answer 156

ANSWER: C COMMENTS: The endocrine pancreas is composed of various cells located in the islets of Langerhans, approximately 1 million of which are interspersed with the acinar and ductal elements throughout the gland. The hormonal peptides produced by the islets affect a wide range of metabolic and physiologic actions. The primary function of the endocrine pancreas is to regulate glucose homeostasis. Beta cells, which are the most numerous, produce insulin. Insulin promotes glucose transport, stimulates protein synthesis, and inhibits glycogenolysis and lipolysis. Alpha cells secrete glucagon, which counterbalances insulin by stimulating hepatic glycogenolysis, gluconeogenesis, ketogenesis, and lipolysis. Glucagon also inhibits intestinal motility and gastric acid and pancreatic exocrine secretion. Somatostatin, produced by delta cells, has a broad range of inhibitory effects on the gastrointestinal tract, including inhibition of secretion of other pancreatic peptides; inhibition of gastric, biliary, intestinal, and pancreatic exocrine secretions; and inhibition of gastrointestinal motility. PP cells are the source of pancreatic polypeptide. Pancreatic polypeptide inhibits pancreatic exocrine secretion and biliary and gut motility. Clinically, deficiency of pancreatic polypeptide has been linked to diabetes following resection of the pancreatic head or chronic pancreatitis. Because postprandial secretion of pancreatic polypeptide is dependent on vagal innervation, it has been used to assess the completeness of vagotomy.

Answer 157

ANSWER: A COMMENTS: The microcirculation of the pancreas is complex and has important correlations with the endocrine and exocrine functions of the gland. The rich anastomotic supply from various sources makes pancreatic ischemia unusual. The islets receive a disproportionately large amount of total pancreatic blood flow (10%–25%) relative to their mass (1%–2%). Both the islets and exocrine tissue have an arteriolar blood supply. The acinar tissue is also perfused by blood that drains from the islets, a mechanism referred to as the islet–acinar or insuloacinar portal system. This system is the structural basis for endocrine regulation of exocrine function. Insulin receptors are present on acinar cells, and the density of receptors is higher on acini located near the islets. Because the islets themselves often have a central-to-peripheral pattern of perfusion, insulin from the centrally located beta cells can influence the other peripheral islet cell types. In addition, some islets are apparently perfused in a peripheral-to-central pattern. CCK and secretin have relatively little effect on the blood flow and thus exert their stimulatory effects independently. Pancreatic blood flow is maintained relatively con- stant despite changes in arterial pressure.

Answer 158

ANSWER: C COMMENTS: Formerly, death from acute pancreatitis often occurred early in the course of the disease as a result of the acute effects of hypovolemia and inadequate resuscitation. In the current era, about 80% of deaths are attributed to secondary pancreatic infection, which develops in approximately 10% of patients with acute pancreatitis. Fatal pancreatic sepsis typically progresses to multisystem organ failure, and deaths occur later in the course of the disease. To have an impact on this disease, therapeutic efforts have therefore focused on the prevention and early diagnosis of pancreatic infection and on more effective methods of surgical therapy.

Answer 159

ANSWER: C COMMENTS: Retroperitoneal infection is a serious, often fatal, complication of acute pancreatitis. The early literature pertaining to the local infectious sequelae of pancreatitis may be confusing because of nonselective use of the term “pancreatic abscess” to describe infectious complications, which vary in severity. Pancreatic abscess best describes a localized collection of drainable pus in or around the pancreas. Pancreatic abscess and infected pseudocyst can be treated effectively by external drainage, and the anticipated mortality rate for each is about 5%. Pancreatic necrosis is a manifestation of severe pancreatitis. When accompanied by infection, it has been associated with a mortality rate that may exceed 40%, which is higher than that for noninfected necrosis. Infected pancreatic necrosis is treated by operative debridement and open or closed retroperitoneal drainage. Patients with sterile necrosis may require operative intervention as well but are generally treated nonoperatively with intensive support as long as their condition permits.

Answer 160

ANSWER: E COMMENTS: Pancreatic infection complicating acute pancreatitis should be suspected in any patient who fails to improve following supportive medical therapy or improves but then demonstrates deterioration. Pancreatic infection occasionally occurs early during the chronologic course of the disease, typically occurring later, as in the patient described. CT is the best method for imaging the pancreas. The results of CT in this patient demonstrate air in the pancreas, which is characteristic of a pancreatic infection. The technique of dynamic pancreatography can identify ischemic areas of pancreas and is useful for evaluating patients who may have pancreatic necrosis. Dynamic pancreatography is performed by serially imaging the pancreas after bolus injection of an intravenous contrast agent. Percutaneous needle aspiration of fluid collections or necrotic areas found on CT can be performed to identify the presence of infection and guide therapeutic decisions about the need for drainage. When pancreatic infection is present, operative drainage and debridement are indicated. Interest has been focused on the selection of closed or open methods of operative drainage. Minimal-access operative approaches are also used to drain and debride pancreatic necrosis in the hope of lowering morbidity in these ill patients. Percutaneous catheters can drain thin fluid but are usually inadequate for the management of infected pancreatic necrosis. Peritoneal lavage has been used early in the course of patients with severe acute pancreatitis. Endoscopic cyst gastrostomy may be appropriate for some patients with pancreatic pseudocysts. These latter two modalities have no role in the man- agement of infected pancreatic necrosis.

Answer 161

ANSWER: A COMMENTS: The risk for infected pancreatic necrosis is related to the clinical severity and duration of disease and to the extent of necrosis. Strategies to decrease secondary pancreatic infection focus on patients at higher risk. Unfortunately, controlled trials of systemic antibiotics for prophylaxis against secondary infection have yielded conflicting results. These differences are probably because of numerous factors, including heterogeneity in the severity of disease, patient characteristics, and concomitant therapy among those studied, as well as differences in study methodologies. Current practice favors systemic antibiotics for patients with severe disease and more extensive (>30%) necrosis based on studies demonstrating fewer septic complications and perhaps decreased mortality. However, not all studies have shown benefit, and the risk for subsequent infection with multiresistant bacterial or fungal organisms may be increased, particularly if prophylactic antibiotic use is prolonged. Because the gut is typically the source of the offending organisms, the use of nonabsorbable enteral antibiotics for selective gut decontamination has had some appeal. The effect of this measure remains unclear, and it is not typically used. Enteric feedings are beneficial to maintain the gut mucosal barrier to bacterial translocation. However, the efficacy of enteric feeding alone for prevention of secondary pancreatic infection has not been demonstrated.

Answer 162

ANSWER: C COMMENTS: Gallstone pancreatitis is related to the passage of stones through the ampulla of Vater. Patients with smaller gallstones have an increased risk for the development of this manifestation. Cholecystectomy is indicated because gallstone pancreatitis is a recurrent problem in 30%–50% of patients if surgery is not performed. The traditional controversy has involved the timing of surgery. Proponents of immediate intervention have found a higher incidence of choledocholithiasis but have not demonstrated that this approach is safer than delayed surgery or that it is necessary for most patients. Most surgeons advise initial nonoperative therapy until the patient’s signs and symptoms subside (most do within 2 to 3 days), followed by elective cholecystectomy with intraoperative imaging of the common bile duct by cholangiography or intraoperative ultrasonography during the same hospitalization. The role of urgent endoscopic retrograde cholangiopancrea- tography and endoscopic sphincterotomy for the management of biliary pancreatitis has been controversial. The vast majority (97%) of patients with gallstone pancreatitis have mild pancreatitis that improves rapidly. ERCP finds common duct stones in only a small percentage of patients and is not indicated routinely. Some trials comparing urgent ERCP and sphincterotomy with traditional treatment have suggested benefit in patients with severe pancreatitis, but this has not been consistently observed. ERCP is indicated for patients with concomitant obstructive jaundice and biliary sepsis. Less invasive methods of duct imaging, such as MRCP or EUS, might be useful in patients at an intermediate risk for choledocholithiasis but are not necessary for most with biliary pancreatitis. For the small proportion of patients with severe biliary pancreatitis, early cholecystectomy should be avoided. Treatment in this group is directed at resolution of the pancreatitis and its complications. When the pancreatitis has subsided, delayed cholecystectomy is indicated.

Answer 163

ANSWER: A COMMENTS: Nutritional support is a critical component of the successful management of patients with severe pancreatitis. Mortality is reduced by positive nitrogen balance. Direct delivery of nutrients into the jejunum is the preferred route. Enteral feeding helps maintain the intestinal mucosal barrier and prevent infection from early bacterial translocation. Enteral feeding is associated with a lower risk for infection and shorter hospital stay than is parenteral nutrition. Moreover, enteric feeding helps avoid catheter-related sepsis and other complications of central venous lines. Recent studies have shown feeding into the stomach to be at least equal to nasojejunal feedings. Oral feeding is cheaper and easier to manage than jejunal feedings. Nasojejunal tubes may require radiologically guided or endoscopic placement. If nutritional goals cannot be met within a few days of initiation, parenteral nutritional support may also be necessary. Intravenous lipids are not detrimental and prevent essential fatty acid deficiency.

Answer 164

ANSWER: C COMMENTS: Pain is the primary indication for surgery in patients with chronic pancreatitis. Selection of the best operation for a particular patient must include consideration of the anatomy of the gland, preexisting endocrine or exocrine dysfunction, compliance and the rehabilitative capacity of the patient, postoperative endocrine or exocrine deficiency, and the likelihood of postoperative pain relief. Patients with small ducts disease are treated by resection if surgery is necessary. Resection of the pancreatic head in properly selected patients has generally yielded better long-term results for pain relief than those yielded by tail resection. The head of the pancreas is often enlarged and bulky in chronic pancreatitis and has been considered to be the “pacemaker” of the disease. A number of operative techniques are available for resection of the pancreatic head including Whipple procedure. This strategy is best employed in patients with calcified obstructive fibrosis of the bile duct, pancreatic duct, and/or duodenum. Other patients with a dilated duct (>6 mm) and without focal findings restricted to the head of the pancreas are candidates for ductal drainage, with lateral pancreaticojejunostomy being the best choice for these procedures. It is important to achieve adequate decompression of the enlarged pancreatic head and uncinate process during drainage procedures. Variations such as the Frey or Beger procedure are intended to accomplish this. The Frey procedure involves patients with increased disease in the head of the pancreas where portions of the head are cored out, and a lateral pancreaticojejunostomy is performed along the opened pancreatic duct. The Beger procedure involves total excision of the head and neck of the pancreas, with a residual edge of pancreas preserving the duodenum and bile duct remains. A loop of jejunum is then brought up, and distal pancreaticojejunostomy as well as a pancre- aticojejunostomy to the residual edge of the pancreas is performed. Further, a jejunojejunostomy is performed for duodenal drainage. Sphincteroplasty does not play a role in the management of patients with established chronic pancreatitis. Total or nearly total (95%) resections have higher long-term morbidity and mortality rates related to postoperative endocrine insufficiency. Although endocrine and exocrine function tends to deteriorate over time in patients with chronic pancreatitis, some evidence suggests that pancreaticojejunostomy halts or delays this decline better than does nonoperative therapy.

Answer 165

ANSWER: A COMMENTS: Peripancreatic fluid collections can be found in about 20% of patients with acute pancreatitis. Many of them resolve spontaneously and should not be mistaken for pancreatic pseudocysts. If the patient is stable, can eat, and does not have clinical evidence of infection or other complications, expectant management is indicated. The fluid collection can be monitored with ultrasonography or CT in 1 to 3 months. If the patient has persistent pain and is unable to eat, nutrition by postpyloric enteral feeding, or parenteral nutrition if necessary, may be instituted for several weeks to allow resolution or maturation of the collection into a pseudocyst. If the patient has a symptomatic or complicated fluid collection that requires early intervention, some method of external drainage must be used. If the fluid is thin, endoscopic or percutaneous catheter drainage may suffice. Operative drainage is preferred if there is substantial necrotic debris, as there often is, or if there is concern about infection. Operative drainage might be accomplished with minimal-access approaches.

Answer 166

ANSWER: A COMMENTS: Historically, pancreatic pseudocysts larger than 5 to 6 cm and present for longer than 6 weeks were thought to have a low rate of spontaneous resolution and a high rate of complications. They were therefore treated by operative drainage. Current understanding of the natural history of pseudocysts is that the rate of spontaneous resolution is higher and the rate of complications is lower than previously thought. Pseudocyst size and duration are therefore no longer absolute criteria for intervention. Rather, pseudocyst-related symptoms are the primary indication for treatment. Large pseudocysts are more likely to be symptomatic and less likely to resolve spontaneously compared with small pseudocysts. In addition, pseudocysts in patients with chronic pancreatitis are unlikely to resolve but may not require intervention if they are stable, asymptomatic, and uncomplicated.

Answer 167

ANSWER: D COMMENTS: Pseudocysts that develop in patients with chronic pancreatitis can be considered mature when they are discovered unless there has also been a recent episode of acute pancreatitis. The indications for treatment of a pancreatic pseudocyst are (1) persistent symptoms (pain, inability to eat, or biliary or gastrointestinal obstruction), (2) enlargement, or (3) the onset of a pseudocyst-related complication (infection, hemorrhage, or rupture). Operative internal pseudocyst drainage into the stomach, jejunum, or duodenum is generally the preferred treatment, depending on the location of the pseudocyst. For patients with chronic pancreatitis, it is critical to evaluate the pancreatic duct to determine whether a concomitant duct drainage procedure is necessary. Pseudocyst drainage can be accomplished laparoscopically in some situations. Pseudocysts in the tail of the gland are sometimes best treated by distal pancreatectomy. Percutaneous or endoscopic drainage of established pseudocysts is still being debated. These techniques can successfully treat pseudocysts in some circumstances but have definite limitations and potential complications.

Answer 168

ANSWER: A COMMENTS: An intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a premalignant condition characterized by papillary projections of mucin-secreting epithelial cells, excessive mucin production, and cystic dilation of the pancreatic duct. The patient may already have cancer when initially seen or may be at some other stage along the process of malignant transformation, which occurs relatively slowly. IPMNs are divided into a main duct type and a branch duct type depending on the areas of the pancreatic ducts that are involved. The goals of evaluation are to identify factors associated with a higher risk for malignancy and to determine the anatomic extent of the disease. EUS is usually the next step in evaluation when IPMN is suspected. EUS can identify diffuse or segmental dilation of the pancreatic duct and the size of cystic lesions or mural nodules and can guide fine-needle aspiration to assess cytology and molecular tumor markers. ERCP shows duct dilation without strictures, filling defects from mucus or nodules, and commonly a patulous papillary orifice with mucus. ERCP also permits sampling of mucus and therapeutic clearance if mucus obstruction is a problem. If available, direct pancreatoscopy and intraductal ultrasound can be adjuncts to ERCP for determining the extent of an IPMN.

Answer 169

ANSWER: B COMMENTS: Progression of IPMN through the adenoma cancer sequence is considered a slow process that requires perhaps 10 to 20 years. Main duct–type tumors have a greater risk for malignancy than the branch duct type. The Sendai Consensus Guidelines identified the following features as risk factors for cancer and as general indicators for resection: main pancreatic duct dilation to greater than 10 mm, cyst size larger than 3 cm, presence of mural nodules, and atypical cytology. Additional risk factors include high-grade dysplasia, multifocal or synchronous tumors, and increasing cyst size during follow-up. In branch duct–type tumors, mural nodularity or atypical cytology may be more important determinants than size.

Answer 170

ANSWER: A COMMENTS: The secretin test of pancreatic exocrine insufficiency is considered the classic testing method. The patient fasts overnight, and the next day, a double-lumen tube is placed into the duodenum through which basal secretion levels are collected for reference. Next, an intravenous bolus of two units of secretin/kg is administered, followed by four 20-min collection periods. Normal levels include 2 mL/kg of pancreatic fluid per hour, bicarbonate concentration of 80 mmol/L, bicarbonate output of 10 mmol/L/h, and amylase of 6 to 18 IU/kg. Bicarbonate is the biggest discriminator between normal patients and dysfunction. “A” represents malnutrition. “B” represents end-stage pancreatitis or advanced pancreatic cancer. “C” is hemochromatosis (associated Zollinger- Ellison syndrome or cirrhosis). “D” is early pancreatic cancer. Other tests that could be performed include 5,5-dimethyl-2,4-oxazolidinedione (DMO), Lundh, or the noninvasive triolein breath test.

Answer 171

ANSWER: B COMMENTS: The etiology for acute pancreatitis is determined in 70%–90% of cases, and thus up to 30% of cases are deemed idiopathic. Further extensive investigation is warranted as over 50% of IAP will recur, increasing a person’s risk of developing chronic pancreatitis. Entities such as biliary sludge/microlithiasis, sphincter of Oddi dysfunction, pancreatic divisum, hereditary pancreatitis, CF, choledochocele, anomalous pancreaticobiliary junction, annular pancreas, and tumors can all be less obvious causes of acute pancreatitis in cases deemed “idiopathic.” Pancreatic divisum is the most common congenital malformation of the pancreas in 5%–8% of the general population. CF is an autosomal recessive disease where a mutation in a regulator gene encoding cyclic adenosine monophosphate regulates chloride ion channels. This disease leads to pancreatitis by diminished pancreatic enzyme secretion in 2% of CF patients.

Answer 172

ANSWER: A COMMENTS: Patients with chronic pancreatitis have an overall higher rate of mortality compared with that of the general population. The 20-year survival after diagnosis is approximately 69%–80% (three- to fourfold higher mortality than general population). Interestingly, the mortality is usually not due to the progression of their pancreatitis to carcinoma, but due to the comorbidities that often go along with patients who suffer from pancreatitis, including alcoholic cirrhosis, diabetes, and smoking-related cardiovascular disease. Of note, patients with chronic pancreatitis have an elevated risk of extrapancreatic malignancy (10%–15%) affecting mostly the upper and lower airways as well as the gastrointestinal tract. The rate of pancreatic cancer is noted to be 1.8% at 10 years postdiagnosis and 4% at 20 years, which is higher than that of the general population (approximately 1.5% lifetime risk).

Answer 173

ANSWER: D COMMENTS: Autoimmune pancreatitis can be very difficult to diagnose and is the cause of acute pancreatitis in 4%–6% of cases. Patient age varies between 30 and 70 years, and it affects men more often than women. The majority (70%–80%) present with painless jaundice. Acute pain, typical of classic pancreatitis, is rare. Additionally, one may see associated symptoms of pancreatic insufficiency, as this disease may have been ongoing without notice. Systemic inflammation/ inflammatory reactions may be associated affecting kidney, lung, biliary tree, salivary glands, and gastrointestinal (GI) tract. Ulcerative colitis is observed in 30% of cases of associated systemic disease. On CT or US, a boggy, thick, “sausage-shaped” pancreas can be seen often with a rim of hypo- or hyperattenuation (early versus late). Irregularities in the intrapancreatic portion of the common bile duct can also be seen. Immunoglobulin G4 levels are thought to be associated with autoimmune pancreatitis, but using levels as a diagnostic marker is highly debated. Antinuclear antibody levels may also be elevated, indicating an autoimmune process. Steroids are considered as standard therapy for this etiology of pancreatitis (typically 30 to 40 mg of prednisone for 1 week).

Answer 174

ANSWER: C COMMENTS: Pancreatic–pleural fistula is a very rare entity and complication of chronic/recurrent pancreatitis. This usually evolves from a disruption in the pancreatic duct (often posterior), followed by fluid tracking in the retroperitoneum and up along the aorta or esophagus into the pleural space. Initial nonoperative therapy can include nil per os status, total parenteral nutrition, repeat thoracentesis, and octreotide. Interventional therapy utilizing ERCP to stent the ductal defect (if present) may also be attempted. Conservative treatment has an efficacy of 30%–60% and a recurrence rate of 15%. Operative therapy for failed conservative therapy, including duct ligation and resection or Roux-en- Y reconstruction, has an efficacy of 90% with an 18% recurrence. Regardless of treatment modality, patients often require prolonged hospitalization. Currently, treatment consists of several weeks of conservative management before progressing to surgical intervention.

Answer 175

ANSWER: A COMMENTS: Discussions over the role of splenectomy have evolved as the quality and frequency of CT scans have risen. Splenic vein thrombosis is thought to occur in 7%–20% of patients with recurrent pancreatitis. This can lead to left-sided portal hypertension and subsequent development of gastric varices. Clinically significant hemorrhage secondary to variceal bleeding occurs in only 4% of those with pancreatitis-induced splenic vein thrombosis. Since not all patients who have splenic vein thrombosis will present with GI hemorrhage, prophylactic splenectomy has fallen out of favor. Splenectomy is now reserved for those who present with hemorrhagic complications of splenic vein thrombosis.

Answer 176

ANSWER: B COMMENTS: This patient has a diagnosis of splenic artery pseudoaneurysm with a likely fistulous connection to a pancreatic pseudocyst. His nausea is likely due to gastric compression from this pseudocyst. As the patient is hemodynamically stable, IR embolization of the aneurysm to prevent further bleeding is the most appropriate next step in management, followed by surgical cystogastrostomy once his bleeding risk is controlled. Rupture is associated with 50% mortality. Planning a cystogastrostomy without management of an associated pseudoaneurysm can lead to intraoperative hemorrhage, delayed hemorrhage, and an increased risk to the patient. Pseudoaneurysms are rare complications (3%–10% incidence) caused by pancreatic enzymes eroding into the surrounding vasculature. The splenic artery is most frequently involved, but reports of involvement of gastroduodenal, pancreaticoduodenal, gastric, and hepatic arteries exist.

Answer 177

ANSWER: D COMMENTS: Several mutations are considered significant and contributory to the development and progression of pancreatic cancer. The aforementioned mutations have all been shown to be involved in this process. Of the mutations mentioned, deletion of the DNA mismatch repair gene occurs least frequently at a rate of 4% in pancreatic cancer. When mutations in DNA mismatch repair genes occur, errors in DNA coding are unable to be repaired. Oncogene p16 is involved in phosphorylation of growth factors and regulatory proteins, and thus loss of this gene leads to unchecked cellular checkpoints. The p53 gene is well studied and involved in a variety of cancers. Its gene product includes a DNA- binding protein that induces apoptosis, thus functioning as a cellular checkpoint. This is inactivated in up to 75% of pancreatic neoplasms. DPC4 is located on chromosome 18q, and this chromosome is missing in 90% of pancreatic cancers. This gene product functions as a tumor suppressor and is specifically mutated in 50% of pancreatic cancers. Of note, BRCA2, well known for its involvement in ovarian and breast cancers, has shown increased risk of pancreatic cancer in those with this mutation.

Answer 178

ANSWER: D COMMENTS: One in 71 people in the United States will develop pancreatic cancer in their lifetime; 5%–10% of these cancer occurrences can be associated with another well-known inherited disorder. FAMMM is an autosomal dominant disorder associated with an increased risk of melanoma and dysplastic nevi. It involves alteration in the gene encoding for p16 protein on chromosome 9p (involved in phosphorylation of growth factors and regulatory proteins, and thus loss of this gene leads to unchecked cellular checkpoints). There is an associated 58% risk of developing pancreatic cancer by age 80 in those affected. FAP is another autosomal dominant gene mutation involving the APC gene, with primary risk involving colon cancer. Associated extracolonic malignancies involve duodenal, thyroid, hepatic, and pancreatic cancers. HNPCC is again primarily associated with colon cancer, with lifetime risk ranging from 52%–82%. The defect involves a mutation in DNA mismatch repair. Extracolonic malignancies include endometrial, ovarian, gastric, and pancreatic cancers (1%–4%; associated medullary histology). ADPKD has not been reliably shown to be associated with pancreatic cancer.

Answer 179

ANSWER: D COMMENTS: Pancreatic cancer is the fourth leading cause of cancer deaths in men and fifth leading cause in women. The classic Whipple procedure (involving antrectomy) is associated with operative mortality rates of 5% in expert hands at high-volume centers. However, it is also associated with morbidity as high as 30%–40% including fistulas, early and late dumping, weight loss, and reflux. An extensive Cochrane review and a meta-analysis of approximately eight randomized clinical trials both support that there is no difference in overall operative morbidity including fistulas, wound infection, postoperative bleeding, biliary leak, or pancreatic leak between the two techniques. There is no difference in operative mortality or oncologic outcome based on procedure type as well. Pylorus-preserving Whipple procedure seems to have lower operative time, less intraoperative blood loss, and decreased need for transfusions compared with pylorus-resecting Whipple procedure, but it does have a higher rate of delayed gastric emptying.

Answer 180

ANSWER: C COMMENTS: Often a debated topic, neoadjuvant versus surgery as the first strategy has been an issue of much interest in the pancreatic surgery community. Some surgeons advocate surgery first in order to attack the disease process early, prevent spread, and work with virgin tissue planes. Others advocate for a neoadjuvant approach for several reasons. One is a possibly improved management of micrometastatic disease. Another reason is to see which patients progress early versus those who would likely benefit from surgery without delaying time to chemotherapy for those who progress aggressively. Clinical trials regarding the neoadjuvant approach boast improved overall survival; however, there is no true randomized trial comparing neoadjuvant to surgery first, as it is difficult to accrue patients when the two treatment arms are so drastically different. A recent review of the American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) data of over 1500 patients with pancreatic cancer does show that patients who underwent neoadjuvant therapy prior to surgi- cal resection had a lower rate of pancreatic fistula (7.3% vs. 15.4%) and deep space infection (3% vs. 10.3%) compared with the surgery- first patients. Also, overall 30-day postoperative morbidity and mortality are reported to be no different in the ACS-NSQIP data set. There is no clear national consensus at this time as to which approach should be the standard of care.

Answer 181

ANSWER: D COMMENTS: Extrapancreatic malignancies have been observed more commonly in patients with IPMN than in those with ductal cancer of the pancreas or other cystic pancreatic neoplasms. The reason for this is not known. No particular genetic predisposition for IPMN has been identified. Extrapancreatic cancer has been reported in approximately one-third of patients with IPMN. Gastric cancer and colon cancer have been the most frequent. No specific guidelines exist, but based on these findings, screening upper gastrointestinal endoscopy and colonoscopy would be appropriate recommendations in these patients. Should an extrapancreatic malignancy be identified, simultaneous resection is often indicated.

Answer 182

ANSWER: D COMMENTS: EUS, in experienced hands, is associated with up to 93% sensitivity and 95% specificity when localizing a suspected neuroendocrine tumor of the pancreas, particularly in the head. Another highly regarded imaging modality with high accuracy (>75%) is somatostatin receptor scintigraphy (SRS; octreotide scan). The accuracy of CT scan alone ranges from 64% to 82%, and MRI is slightly better at above 74% sensitivity, similar to SRS. Limits of EUS include the inability to evaluate the liver for disease. Thus when using EUS to localize neuroendocrine tumors of the pancreas, SRS or another imaging modality would be needed to evaluate for metastatic disease.

Answer 183

ANSWER: C COMMENTS: Insulinoma is the most common functional neoplasm of the endocrine pancreas and is evenly distributed throughout the pancreas; 10% of insulinomas are associated with MEN-1, 10% are malignant, and 90% are sporadic and solitary. Patients present with symptoms of hypoglycemia during fasting, low levels of glucose less than 50 mg/dL, and relief of symptoms with exogenous glucose (referred to as “Whipple triad”). Symptoms can include findings associated with catecholamine surge including palpitations, diaphoresis, and tachycardia. Also, neurologic symptoms such as confusion, seizures, and irritability may be observed. Differential diagnosis can include tumors, such as mesothelioma and sarcoma, adrenal insufficiency, and self-administration of insulin. In order to make the diagnosis of insulinoma, first a 24-h monitored fast should be performed. This includes glucose and insulin samples every 4 to 6 h in addition to samples at any time that symptoms appear during this period. Insulin-to-glucose ratios greater than 0.4 (normal are less than 0.3) after a prolonged fast are highly sensitive for the diagnosis. Levels of C-peptide and proinsulin are elevated often in these patients as well but are not so in patients who self-administer insulin. The absolute diagnosis is made with these six key features: (1) displayed blood glucose levels ≤ 40 mg/dL, (2) concomitant insulin levels ≥ 3 U/L, (3) C-peptide levels ≥ 200 pmol/L, (4) proinsulin levels ≥ 5 pmol/L, (5) β-hydroxybutyrate levels ≤ 2.7 mmol/L, and (6) absence of sulfonylurea (metabolites) in the plasma or urine.

Answer 184

Duval-Zollinger: Caudal pancreaticojejunostomy Partington-Rochelle: Modification of the Puestow-Gillesby procedure of longitudinal pancreaticojejunostomy, that does not include a caudal pancreatectomy Puestow-Gillesby: Longitudinal roux-en-y pancreaticojejunostomy (invaginating anastomosis between pancreas and jejunum, after amputating the tail of the pancreas and opening the duct along its long axis)

Answer 185

Fry and Child: 95% distal pancreatectomy (preserves rim of the pancreas In the pancreaticoduodenal groove, along with Its associated blood vessels and distal CBD) Kausch-Whipple: Pancreaticoduodenectomy Priestley: Total pancreatectomy

Answer 186

Beger: Duodenum-preserving pancreatic head resection (DPHR) Frey and Smith: Local resection of pancreatic head with longitudinal pancreaticojejunostomy (LR-LPJ) Hamburg: Modification of the LR-LPJ procedure (wider excavation of the pancreatic head is created In continuity with the dorsal dochotomy, followed by a single, side to side pancreaticojejunostomy) Berne: Modification of the Beger procedure (excavation of the central portion of the head without formal division of the pancreatic neck)

Answer 187

Pancreatitis (75%) | Trauma (25%)

Answer 188

1) Resection of pancreatic or duodenal primary 2) Gastrojejunostomy (or duodenojejunostomy) 3) Hepaticojejunostomy 4) Pancreaticojejunostomy 5) Cholecystectomy

Answer 189

1) Biliary obstruction - Endoscopic biliary metal stent (preferred) - Percutaneous biliary drainage with subsequent internalization - Open biliary enteric bypass 2) Gastric outlet obstruction Good performance status: - Gastrojejunostomy (Open/Lap) +/- tube jejunostomy - Consider enteral stent Poor performance status: - Enteral stent - Percutaneous endoscopic gastrostomy (PEG) tube 3) Severe tumor-associated abdominal pain - EUS-guided celiac plexus neurolysis (fluoroscopic or CT-guided if unavailable) - Consider palliative radiation +/- chemo if not already given 4) Depression, pain, malnutrition - Palliative medicine service evaluation - Nutritional evaluation 5) Pancreatic Insufficiency - Pancreatic enzyme replacement 6) Thromboembolic disease - Low molecular weight heparin (preferred over warfarin)

Answer 190

1) Symptomatic fasting hypoglycemia 2) Serum glucose <50mg/dL 3) Relief of symptoms with glucose administration

Answer 191

Simple enucleation

Answer 192

1) Close to main pancreatic duct | 2) >2cm

Answer 193

Pancreatic tail

Answer 194

Debulking (as palliative treatment)

Answer 195

Body and tail

Answer 196

Caudal pancreaticojejunostomy *Drainage

Answer 197

Longitudinal roux-en-y pancreaticojejunostomy (invaginating anastomosis between pancreas and jejunum after amputating the tail of the pancreas, and opening the duct along its long axis) *Drainage

Answer 198

Modification of the Puestow-Gillesby procedure of longitudinal pancreaticojejunostomy that does not include a caudal pancreatectomy *Drainage

Answer 199

95% distal pancreatectomy (preserves the rim of pancreas in the pancreaticoduodenal groove, along with its associated blood vessels and distal common bile duct) *Resectional

Answer 200

Pancreaticoduodenectomy *Resectional

Answer 201

Total pancreatectomy *Resectional

Answer 202

Duodenum-preserving pancreatic head resection (DPHR) *Drainage+Resection

Answer 203

Local resection of the pancreatic head with longitudinal pancreaticojejunostomy (LR-LPJ) *Drainage+Resection

Answer 204

Modification of the LR-LPJ procedure (wider excavation of the pancreatic head is created in continuity with the dorsal dichotomy followed by a single, side-to-side pancreaticojejunostomy) *Drainage+Resection

Answer 205

Modification of the Beger procedure (excavation of the central portion of the head without formal division of the pancreatic neck)

Answer 206

Pancreatitis (75%) | Trauma (25%)

Answer 207

1) Exposure of infra pancreatic SMV 2) Extended Kocher maneuver 3) Portal dissection 4) Transect stomach (antrectomy) 5) Transect jejunum and dissect ligament of Treitz, rotating duodenum under mesenteric vessels 6) Transect pancreas and complete retroperitoneal dissection by removing specimen from SMV and SMA.

Answer 208

1) Endoscopic biliary metal stent (preferred) 2) Percutaneous biliary drainage 3) Open biliary enteric bypass

Answer 209

Good performance status 1) Gastrojejunostomy +/- jejunostomy tube 2) Enteral stent Poor performance status 1) Enteral stent 2) Percutaneous endoscopic gastrostomy (PEG) tube

Answer 210

1) EUS-guided celiac plexus neurolysis (fluoroscopic or CT-guided if unavailable) 2) Palliative radiation +/- chemotherapy

Answer 211

1) Palliative medicine service evaluation | 2) Nutritional evaluation

Answer 212

Pancreatic enzyme replacement

Answer 213

Low molecular weight heparin (preferred over warfarin)

Answer 214

``` AKA NESIDEOBLASTOSIS: 1) Beta-cell hypertrophy 2) Islet-cell hyperplasia 3) Increased beta-cell mass + 1) Ectopic islet tissue 2) Multilobulated islets 3) Ductoinsular complexes ``` Nesideoblastosis with hyperinsulinism was previously considered a disease of neonates, where subtotal/total pancreatectomy was required to correct potentially fatal neonatal hyperinsulinism. However, this has now been reported in patients 2-5 years after Roux-en-y gastric bypass for obesity. This appears to result from an idiosyncratically-prolonged hyper secretion of the incretin hormones GIP and GLP-1 after the gastric bypass. GLP-1 is a potent stimulant of the expression of the transcription factor PDX-1, which normally regulates beta-cell development and growth. Treatment to prevent episodes of hypoglycemia is conversion of the gastric bypass to a form of bariatric procedure that restores normal intestinal flow of nutrients, such as the gastric sleeve, or the addition of a restriction element such as an adjustable gastric band.

Answer 215

AKA PET or pNET (pancreatic neuroendocrine tumors) are most often malignant, because they have the potential for uncontrolled growth and metastasis. Dx: 1) Clinical - Vague pain - Weight loss 2) CT - Incidental finding (asymptomatic) - Enhances with arterial contrast - Cystic component (central necrosis) 3) Somatostatin receptor scintigraphy (Octreoscan) - Helpful in staging the disease Tx: 1) Surgical resection with splenectomy - Body and tail tumors 2) Observation - small indolent nonfunctional pNETs (<2cm) 3) Adjuvant platinum-based chemotherapy - for high-grade (poorly-differentiated) pNET Follow-up: - CT scan or ocreotide scan annually x 5 years after resection