GI 4

Question 1

Injury to _____ cells in the _______ portion of the pancreas leads to an inflammatory condition known as pancreatitis.

Answer 1

injury to acini cells in the exocrine portion –> pancreatitis

Question 2

Acute pancreatitis varies from a mild, self-limited condition with acute inflammation and stromal _______ to a severe, acute _________ disorder with massive necrosis and may be fatal.

Answer 2

stromal edema

acute hemorrhagic disorder that can be fatal

Question 3

What can repeated episodes of acute pancreatitis lead to?

Answer 3

Chronic pancreatitis

Question 4

Describe three characteristics of chronic pancreatitis.

Answer 4

1. Recurrent severe abdominal pain.
2. Progressive fibrosis.
3. Pancreatic insufficiency (eventually).

Question 5

Are either acute or chronic pancreatitis reversible?

Answer 5

Acute is if underlying cause is removed. Chronic is not - there is irreversible destruction of the parenchyma, especially the exocrine portion.

Question 6

Name six causes of pancreatitis.

Answer 6

1. Inappropriate activation of pancreatic enzymes.
2. Duct obstruction.
3. Gallstones.
4. Alcohol abuse.
5. Other: Viral infections, drugs, trauma, hyperlipidemia or calcemia.
6. Idiopathic (unknown) - makes up 10-20% of cases.

Question 7

What type of necrosis would be seen in a case of pancreatitis caused by inappropriate activation of enzymes?

Answer 7

Fat necrosis.

Question 8

Name some plasma protease inhibitors that are supposed to provide protection against pancreatic enzyme activation.

Answer 8

1. a1-antitrypsin
2. a2-macroglobulin
3. C1 esterase inhibitor
4. Pancreatic secretory trypsin inhibitor.

Question 9

Injury to acinar cells in the pancreas leads to ________ activation, which starts a cascade of proteolytic _________ activations.

Answer 9

Leads to trypsin activation, trypsin activates a bunch of other enzymes (biochem)

Question 10

___% of patients with acute pancreatitis have gallstones, while only ____% of people with gallstones develop acute pancreatitis.

Answer 10

45% with acute pancreatitis have gallstones but only 5% of people with gallstones get acute pancreatitis.

Question 11

Having gallstone(s) increases risk for development of acute pancreatitis by ____ times.

Answer 11

25

Question 12

What proportion of acute pancreatitis cases are associated with alcohol abuse? What percentage of alcoholics develop acute pancreatitis?

Answer 12

1/3 are associated with alcohol abuse.

5% of alcoholics develop acute pancreatitis.

Question 13

Ethanol causes spasm or acute edema of the ______ of _____. Ethanol is also thought to stimulate the pancreas to release ________ without concomitantly increased fluid.

Answer 13

sphincter of Oddi.

Ethanol triggers release of pancreatic enzymes without concomitantly increased fluid.

Question 14

Describe the macroscopic changes associated with acute pancreatitis.

Answer 14

Edema, hyperemia at first, leading to hemorrhagic foci.

Severe cases: Organ is destroyed and converted into a retroperitoneal hematoma.

Question 15

Describe the 5 microscopic changes associated with acute pancreatitis.

Answer 15

1. Edema
2. Fat necrosis with calcium deposits, saponification, involvement of extrapancreatic fat.
3. Acini cell necrosis.
4. Intense acute inflammation.
5. Destruction of blood vessels with extravasation of RBCs.

Question 16

List 5 clinical features of acute pancreatitis. What percentage are mild, and what percentage are severe/life-threatening?

Answer 16

1. Severe epigastric (upper abdominal) and upper back pain.
2. Nausea and vomiting
3. Vascular collapse/shock from hemorrage of destroyed vessels.
4. Elevated serum amylase/lipase.
5. Gram-negative bacteria infection.

Usually mild/self limiting, but 20% severe and a medical emergency

Question 17

___% of patients experience repeat episodes of acute pancreatitis, leading to chronic pancreatitis. This disease is characterized by abdominal/back pain, weight loss, and jaundice. ________ is visible in radiographs. In ___% of cases it is fatal.

Answer 17

5% get chronic pancreatitis.

Calcification is visible in radiographs.

20% die from it.

Question 18

____% of patients who survive acute pancreatitis, especially alcoholic pancreatitis, go on to develop a pancreatic _________

Answer 18

50% develop a pancreatic pseudocyst

Question 19

What is a pancreatic pseudocyst?

Answer 19

Complication of acute pancreatitis: A circumscribed collection of fluid rich in pancreatic enzymes, blood, and necrotic tissue, typically located in the lesser sac of the abdomen.

Question 20

Do pancreatic pseudocysts have epithelial linings? How big are they? Can they become infected?

Answer 20

No epithelial lining. 2-30 cm. Can become infected and form an abscess.

Question 21

Name the three major causes of acute pancreatitis.

Answer 21

1. Alcohol in 2/3 of adult cases.
2. Pancreatic duct obstruction.
3. Chronic injury to acinar cells as in hemochromatosis.

Question 22

Describe two microscopic changes seen in chronic pancreatitis.

Answer 22

1. Fibrosis - reduction in functional parenchyma (acinar and islet cell loss).
2. Dilation of ducts.

Question 23

What are the two types of pancreatic cystic neoplasms?

Answer 23

Serous cystadenomas and mucinous cystic neoplasms.

Question 24

What percentage of pancreatic cysts are neoplastic?

Answer 24

5 to 15%

Question 25

Describe four characteristics of serous cystadenomas of the pancreas.

Answer 25

1. Glycogen-rich cuboidal cells surrounding cysts with clear, straw-colored (yellowish) fluid.
2. Begins in 7th decade of life.
3. Female/male ratio 2:1
4. Benign

Question 26

Describe five characteristics of a mucinous cystic neoplasm of the pancreas.

Answer 26

1. Almost always in women.
2. In body or tail of pancreas.
3. Cystic space filled with thick, tenacious mucin.
4. Lined by columnar mucinous epithelium with dense cellular stroma.
5. Can be benign, borderline malignant, or malignant.

Question 27

Has the five year survival rate from pancreatic cancer increased over the last 40 years?

Answer 27

Not really (from 3% in 1975 to 5% in 2004)

Question 28

Pancreatic cancer is the ___th most common cause of cancer death in men and women in the U.S.

Answer 28

4th

Question 29

What is the five year survival rate of pancreatic cancer?

Answer 29

5%

Question 30

What type of pancreatic cancer makes up 90% of cases?

Answer 30

ductal adenocarcinoma.

Question 31

At what age is pancreatic cancer most commonly seen?

Answer 31

> 60 years of age.

Question 32

What two conditions/habits are thought to be associated with the development of pancreatic cancer?

Answer 32

1. Smoking associated in 25% of cases.

2. DM seen in 80% of cases.

Question 33

___% of pancreatic cancers are found in the head of the pancreas, ___% are found in the body, and ___% are found in the tail. Cancers of the body and tail ______ (do or do not) impinge on the biliary tract and therefore may remain silent for a while.

Answer 33

60% in head
10% in body
5% in tail
the rest are diffused

cancers of body or tail do not impinge on biliary tract

Question 34

There are four mutations that are often seen in pancreatic cancer cases. List them and briefly describe each.

Answer 34

1. K-RAS – early event; most frequently altered oncogene.
2. p16 – most frequently inactivated tumor suppressor gene.
3. SMAD4 – tumor suppressor gene inactivated in 55% of cases.
4. p53 – tumor suppressor gene inactivated in 50-70% of cases; late event.

Question 35

Where does pancreatic cancer most often metastasize to (2)?

Answer 35

Regional lymph nodes and liver.

Question 36

Is the order of occurrence of mutations important in the development of pancreatic cancer?

Answer 36

No, just the accumulation is what is needed for development of the disease.

Question 37

Describe clinical features of pancreatic cancer.

Answer 37

1. Weight loss/anorexia.
2. Epigastric pain, often radiating to the back.
3. Jaundice in 50% of patients with cancer in the pancreatic head.
4. Courvorier sign: Acute, painless gallbladder dilation accompanied by jaundice as a result of comomon bile duct obstruction by the tumor.
5. Migratory thrombophlebitis: Deep venous thrombosis or Trosseau syndrome seen in 10% of pts, especially with body and tail cancers.

Question 38

Pancreatic endocrine tumors (PETS) account for ___% of all pancreatic neoplasms.

Answer 38

10%

Question 39

What is the most common islet cell neoplasm?

Answer 39

Insulinoma (beta cell tumors) account for 75% of islet cell neoplasms.

Question 40

Describe the morphological changes of an insulinoma.

Answer 40

They resemble normal beta cells but form trabecular and solid patterns. Amyloid found in stroma.

Question 41

Most insulinomas are benign lesions in the _____ or _____ of the pancreas.

Answer 41

body or tail

Question 42

What clinical features are associated with insulinoma?

Answer 42

1. Severe hypoglycemia.
2. Sweating, nervousness, hunger, confusion, lethargy, coma.
3. High levels of insulin in blood and in tumor cells.

Question 43

Other than insulinoma (beta cells), name four other islet cell tumors.

Answer 43

1. Gastrinomas (G cell tumor)
2. Glucagonomas (alpha cell tumor)
3. Somatostatinoma (delta cell tumor)
4. Vasointestinal polypeptide-secreting tumors (VIPomas)

Question 44

Describe clinical features of gastrinomas.

Answer 44

G cell tumor, hypersecretion of gastrin which triggers release of gastric acid from parietal cells leading to peptic ulceration of duodenum and jejunum. Most are malignant.

Question 45

Describe clinical features of glucagonomas.

Answer 45

Alpha cell tumor. Mild diabetes, necrotizing migratory & erythematous rash, anemia, venous thrombosis. Glucagon levels 30x higher than normal. 2/3 are malignant.

Question 46

Describe clinical features of somatostatinomas.

Answer 46

Delta cell tumor - excess somatostatin (normally functions to inhibit insulin and glucagon release). Mild diabetes, gallstones, steatorrhea. Most are malignant.

Question 47

Describe clinical features of Vasointestinal polypeptide-secreting tumors (VIPomas).

Answer 47

Elevated levels of VIP. Explosive diarrhea. Most are malignant.