Chapter 19: The Pancreas Flashcards
What is the most common congenital anomaly of the pancreas?
What occurs embryologically?
- Pancreas Divisum
- Failure of fusion of fetal duct system of the dorsal and ventral pancreatic primordia

In Pancreas Divisum the bulk of the pancreas (formed by dorsal primordium) drains through where?
Through the small-caliber minor papilla

Annular pancreas is caused by what?
Can lead to what complication?
- A band-like ring of normal pancreatic tissue completely encircles the 2nd portion of the duodenum
- Can produce duodenal obstruction
Very rarely the pancreas fails to develop (agenesis) and sometimes is due to germline mutation involving which gene?
PDX1
*‘P’ for pancreas!
In Western countries which 2 factors account for the majority of acute pancreatitis?
- Biliary tract disease
- Alcoholism
Pancreatic duct obstruction leading to acute pancreatitis is most commonly due to?
What are 4 other risk factors that cause obstruction?
- Gallstones = most common
- Periampullary neoplasms
- Choledochoceles
- Parasites —> Ascaris lumbricoides + Clonorchis sinensis
- Possible pancreas divisum
Local fat necrosis in acute pancreatitis is caused by what?
Lipase is produced in an active form –> local fat necrosis
Which ion plays a key role in regulating trypsin activation?
Ca2+
How do low Ca2+ levels vs. high Ca2+ levels have an affect on trypsin?
- High Ca2+ –> loss of autoinhibition = trypsin activation
- Low Ca2+ –> trypsin cleaves and inactivates itself = inactivation
How does primary acinar cell injury play a role in the pathogenesis of acute pancreatitis?
i.e., role of oxidative stress, what’s activated and which TF’s expressed
- Oxidative stress may generate free radicals –> membrane lipid oxidation + activation of TF’s such as AP1 and NF-kB
- Increased Ca2+ flux leads to increased Trypsin
Alcohol consumption causes a transient increase in the contraction of what?
Sphincter of Oddi
Which 3 metabolic disorders are implicated in the development of acute pancreatitis?
- Hypertriglyceridemia
- Hypercalcemic states
- Hyperparathyroidism –> increased Ca2+
Which virus has been linked to pancreatitis?
Mumps - Paramyxovirus - ssRNA virus
Hereditary pancreatitis due to a trypsinogen mutation has what type of inheritance pattern?
Which gene is mutated and is it a loss or gain of function?
- Autosomal Dominant
- Gain-of-function in PRSS1 (chromosome 7) –> Trypsinogen gene
Hereditary pancreatitis can also be caused by a loss-of-function mutation in which gene?
Inheritance pattern of this mutation?
- SPINK1 (chromosome 5) –> encodes a trypsin inhibitor
- Autosomal recessive
How do mutations in the CFTR gene lead to potential duct obstruction and the development of pancreatitis?
Decreased HCO3- secretion by ductal cells –> promotes protein plugging + duct obstruction
In the milder form, acute interstitial pancreatitis, what are the 3 histologic alterations seen?
- Mild inflammation
- Interstitial edema
- Focal areas of fat necrosis (due to lipase)

In the more severe form, acute necrotizing pancreatitis, what are some of the characteristic histological changes?
Which cells are necrosed?
- Necrosis of acinar and ductal tissues + islets of Langerhans
- Vascular injury –> hemorrhage into pancreatic parenchyma
What is the cardinal clinical symptom of acute pancreatitis?
Where does this pain refer to and how is it characterized?
- Abdominal pain
- Constant + intense –> referred to upper back or left shoulder
Elevated plasma levels of what support the diagnosis of acute pancreatitis?
Describe the timeline of these elevations (first 24 hours to 96 hours)?
- Elevation of amylase during the first 24 hours
- Rising lipase level by 72 to 96 hours
Full-blown acute pancreatitis is a medical emergency and how does it typically manifest clinically?
What causes the serious systemic complications and what are these complications that may be seen?
- Sudden disasterous onset of “acute abdomen”
- Release of toxic enzymes, cytokines, and other mediators into circulation —> leukocytosis, DIC, edema, and acute respiratory distress syndrome
- Shock and acute renal tubular necrosis may occur
What is the key to management of someone who presents with acute pancreatitis?
“Resting” the pancreas by total restriction of oral intake and by supportive therapy w/ IV fluids + analgesia
What are 2 ominous complications that can arise with acute pancreatitis?
- Acute respiratory distress syndrome
- Acute renal failure
How does acute vs. chronic pancreatitis differ in the type of injury that occurs to the pancreatic parenchyma (ie., reversible or irreversible)
- Acute is associated with reversible injury
- Chronic is associated with irreversible injury
Which patient population (age and sex) is most commonly affected by chronic pancreatitis?
What is the most common cause?
- Middle-aged males
- Long-term alcohol abuse
While many of the cytokines produced during acute and chronic pancreatitis are similar, which type tends to predominate in chronic pancreatitis?
Leads to activation of?
- Fibrogenic –> TGF-β and PDGF
- Activation and proliferation of periacinar myofibroblasts (pancreatic stellate cells)
The activation of pancreatic stellate cells in chronic pancreatitis results in the deposition of?
Collagen and fibrosis
Autoimmune pancreatitis is a distinct form of chronic pancreatitis associated with the presence of which cells in the pancreas?
IgG4-secreting plasma cells
Why is it important to be able to differentiate Autoimmune Pancreatitis from a Pancreatic Carcinoma?
Autoimmune pancreatitis RESPONDS to steroid therapy
Which type of pancreatitis is characterized by fibrosis, atrophy and dropout of acini, and variable dilation of pancreatic ducts?
Chronic pancreatitis
Chronic pancreatitis caused by alcohol abuse is characterized by which histologic findings?
- Ductal dilation
- Intraluminal protein plugs and calcifications

Chronic pancreatitis may present in many different ways, such as?
May be precipitated by?
- Following repeat bouts of acute pancreatitis
- Repeat attacks of mild-moderately severe abdominal pain or persistent abdominal pain
- Attacks may be precipated by alcohol abuse, overeating, or the use of opioids + other drugs
- Malabsorption sx’s (steatorrhea) or DM
In some patients, chronic pancreatitis may be clinically silent until the development of what?
- Pancreatic insufficiency –> steatorrhea
- Diabetes mellitus (due to destruction of exocrine and endocrine pancrease)
Diagnosis of chronic pancreatitis requires a high degree of suspicion, but which finding on CT and ultrasound can be very helpful?
Calcifications with pancreas
Which type of pancreatitis is associated with a 40% lifetime risk of developing pancreatic cancer?
Hereditary pancreatitis
Pseudocysts of the pancreas are localized collections of what?
They are rich in?
Lack?
- Collections of necrotic and hemorrhagic material
- Rich in pancreatic enzymes
- Lack and epithelial lining
Pseudocysts of the pancreas typically arise following?
May also arise as a result of?
- Bout of acute pancreatitis, particularly one superimposed on chronic alcoholic pancreatitis
- Trauma
Pseudocysts may be situated within the pancreas but are more commonly found where?
- Lesser omental sac
- Retroperitoneum btw stomach and transverse colon
- Or btw stomach and liver
When areas of intrapancreatic or peripancreatic hemorrhage are walled off by fibrous tissue and granulation tissue, this forms what?
Pseudocysts
What is the 5-year survival rate for Pancreatic Carcinoma (aka infiltrating ductal adenocarcinoma)?
<5%; poor
Invasive pancreatic cancers are believed to arise from which well-defined noninvasive precursor lesions in small ducts?
Pancreatic intraepithelial neoplasia (PanIN)
Which is the most frequently altered oncogene in pancreatic cancer?
Which chromosome is it on?
KRAS - Cr. 12p
Mutations in KRAS signaling associated w/ pancreatic cancer most notably leads to activation of which 2 pathways?
MAPK and PI3K/AKT-pathways
What is the most frequently inactivated tumor suppressor gene in pancreatic cancers?
Which chromosome is it on?
- CDKN2A/p16
- Cr. 9p
Which tumor suppressor gene is inactivated in 55% of pancreatic cancers and encodes a protein essential for TGF-β signaling?
SMAD4 on Cr. 18q
Hypermethylation of the promoter of which tumor suppressor gene has been implicated in pancreatic cancer?
CDKN2A
What is the typical age range for the onset of pancreatic cancer?
More commonly seen in which ethnicities?
- Age 60-80 yo
- More common in blacks and Ashkenazi Jews (BRCA2)
What is the strongest enviornmental risk factor for the development of pancreatic cancer?
Cigarette smoking doubles the risk
*Consumption of diet rich in fats also been implicated
What are 2 risk factors for pancreatic cancer, which may also be complications of the development of cancer?
- Chronic pancreatitis
- Diabetes mellitus
New-onset DM in an older patient (60-80 yo) may be the first sign that they have?
Pancreatic cancer
Germline mutations in which gene is associated with familial atypical multiple-mole melanoma syndrome and almost always the development of pancreatic cancer?
CDKN2A
The majority of pancreatic cancers arise in which part of the pancreas?
Head (60%) > Body (15%) > Tail (5%)
The vast majority of pancreatic cancers take the form of?
Ductal adenocarinomas
What are 2 features characteristic of pancreatic cancer (i.e., behavior and reaction elicited)?
- Highly invasive (even “early” invasive pancreatic cancers extensively invade peripancreatic tissue)
- Elicits an intense host reaction in the form of dense fibrosis (“desmoplastic response”)
Majority of the carcinomas of the head of the pancreas obstruct what?
Leads to which clinical signs and symptoms?
- Distal common bile duct
- Marked distention of biliary tree + Obstructive Jaundice
Why do pancreatic cancers of the body and tail often remain silent for some time?
Do not impinge on the biliary tract like those of the head
Pancreatic cancers often grow along whicn structures and can directly invade into which organs/structures?
- Often along blood vessels and nerves
- Directly into: spleen, adrenals, transverse colon, and stomach
Which 2 sites are the primary sites for distant metastases by pancreatic cancer?
- Liver
- Lungs
Which disorder is associated with the highest increased risk (130-fold) for the development of pancreatic cancer?
What is the associated gene?
- Peutz-Jegher syndrome
- STK11
Which colorectal cancer is associated with an increased risk for pancreatic cancer?
Associated genes?
- HNPCC
- MLH1, MSH2
Carcinomas of the pancreas typically remain silent until what occurs; producing what initial symptom?
Symptoms of advanced disease?
- Until invasion occurs
- Pain is usually the 1st symptom, but by this time the cancer is usually beyond cure
- Weight loss, anorexia, and generalized malaise = cachexia = advanced disease
Which “sign” is seen in a small % of patients with pancreatic cancer?
Migratory thrombophlebitis or the Trousseau sign

Which elevated serum markers associated with pancreatic cancer can be used to assess a pts response to treatment?
Are they specific and sensitive?
- Carcinoembryonic antigen
- CA19-9 antigen
*Non-specific and lack sensitivity needed to be used as tests to screen the wider population
Which rare pancreatic tumor occurs in children and what are its distinct microscopic findings?
- Pancreatoblastoma
- Squamous islands admixed with acinar cells
*Metastatic but better prognosis than pancreatic ductal cell carcinomas
What is the hallmark of pancreatic cancer?
Intense desmoplastc rxn w/ dense stromal fibrosis