Pancreas

Question 1

Pancreatic neuroendocrine tumor

Answer 1

Def:
* islet cell tumors

Caused by:
* neoplasm that arise from the endocrine pancreas that actively secretes hormones to have systemic effect

Histology:
* salt-pepper chromatin ( indicative of neuroendocrine differentiation)

Question 2

Gastrinoma

Answer 2

Def:

• second most common PNET
• Gastrin secreting tumor of the endocrine pancreas (can also occur in the duodenum of GI) (2 places )
• associated with Zollinger- Ellison Syndrome

Pathway:

1. gastrin normally comes from the G-cells that are not found in the endocrine pancreas
2. gastrin induces gastric acid secretion

Lead to :

• causes recurrent ulcers in the stomach, duodenum, jejunum (don’t usually get ulcer that far down)
  * * ulcer don’t respond to conventional therapy

Sign/symptoms:

1. Abdominal pain
2. Diarrhea

Diagnosis:

1. Diagnose with failed suppression by secretin, which normally inhibits gastrin release
2. high blood gastrin levels

Treatment:

1. Somatostatin (octreotide)
2. Surgical resection

Question 3

Insulinoma

Answer 3

Def:

• most common PNET
• insulin secreting tumor of the endocrine pancreas (beta cells)

Sign/symptoms:

1. Hypoglycemia symptoms ( hungry, nervous, sweating —> progress to lethargy, confusion, coma)
2. Whipple’s triad:
   
   1. Hypoglycemia ( sugar below 55)
   2. Symptoms of hypoglycemia
   3. Symptoms corrected with administration of glucose

Diagnosis:

1. Low glucose
2. High insulin
3. High C-peptide (rule out exogenous use of insulin injection)

Pathology:
* usually small cell

Treatment:
*surgical resection

Question 4

Glucagonoma

Answer 4

Def:

• rare tumor, often malignant
• glucagon secreting tumor of endocrine pancreas (alpha cells)

Sign/symptoms:

1. Mild diabetes
2. Dermatitis (necrolytic migratory erthyma) on the groin area
3. Decreased weight
4. Decreased RBCs (anemia)
5. Venous thrombosis (DVT)

Diagnosis:

1. Increased glucagon
2. Increased glucose

Treatment:

1. Somatostatin (octreotide)
2. Surgical resection

Question 5

VIPoma

Answer 5

Def:

• AKA Verner-Morrison Syndrome
• rare tumor, most are malignant
• VIP secreting tumor of the endocrine pancreas ( D1 cells)

Mechanism:

• Vasoactive intestinal Peptide (VIP)
  
  1. Normal role in gut is to stimulate secretion of water & electrolytes

Sign/symptoms:

1. Profuse & explosive watery diarrhea
2. Dehydration

Diagnosis:

1. Low HCL (hypochlorhydria)
2. Low K

Question 6

Somatostatinoma

Answer 6

Def:

• rare tumor, most are malignant
• somatostatin secreting tumor of endocrine pancreas ( D or Delta cells)

Mechanism:
1. Somatostatin inhibits: Gastrin, Cholecystokinin (CKK), Secretin, Motilin, Vasoactive intestinal Peptide (VIP), Gastric inhibitory peptide (GIP), & Enteroglucagon

Sign/symptoms:

1. Mild diabetes
2. Gallstone
3. Steatorrhea
4. Hypochlorhydria

Treatment:

1. Somatostatin (octreotide)
2. Surgical resection

Question 7

Octreotide (somatostatin)

Answer 7

1. Somatostatin analog
2. More potent than somatostatin (40 times, long acting)
3. Uses:
   
   1. Acromegaly
   2. Secretory diarrhea (associated with carcinoid,
      AIDS, Cancer chemotherapy or diabetes)
   3. Esophageal variceal (bleeding)

Adverse effect:

1. Abdominal pain
2. N/V
3. Steatorrhea
4. Gallstone (due to biliary statsis)

Question 8

Conventional therapy of peptic ulcer

Answer 8

The recommended standard first-line therapy is :

1. either a bismuth-containing quadruple therapy for 14 days (PPI, a bismuth salt, tetracycline, and metronidazole)
2. or a 14-day concomitant therapy for patients intolerant of bismuth (PPI, clarithromycin, amoxicillin, and metronidazole)

both regimens yield eradication rates

Question 9

Multiple Endocrine Neoplasia (MEN)

Answer 9

MEN 1:

1. Pituitary Adenoma
2. Parathyroid hyperplasia
3. Pancreatic tumor

MEN 2A:

1. Parathyroid hyperplasia
2. Medullary thyroid carcinoma
3. Pheochromocytoma

MEN 2B:

1. Mucosal neuroma
2. Marfanoid body habitus
3. Medullary thyroid carcinoma
4. Pheochromocytoma