Chapter 15: Endocrine Pancreas

Question 1

What do alpha, beta, and delta cells make?

What are pancreatic polypeptide secreting cells?

Answer 1

Alpha: Periphery of islets, glucagon. Glycogenolysis and gluconeogenesis in the liver.

Beta: Center, insulin. Polygonal and rhomboidal crystals.

Delta: Somatostatin.

Pancreatic polypeptide-secreting cells: Polypeptide - enzyme secretion by gastric mucosa, smooth muscle contraction in intestine and gallbladder, gastric acid and secretion by exocrine pancreas and biliary system.

Question 2

What genes are involved in pancreatic neuroendocriene tumors?

Answer 2

MEN-1 (with parathyroid, pituitary, and pancreatic tumors)

VHL - usually nonfunctioning

May produce hormones not ordinarily produced by pancreas - ACTH, PTH, calcitonin, vasopressin.

Organoid-patterns: Nests, ribbons, glands, festoons.

Immunohistochemistry shows chromogranin A and synaptophysin - endocrine tumor.

Question 3

Patient presents sweating, visual changes, confusion, nervousness, and hunger. Laboratory testing reveals hypoglycemia and an elegated serum insulin and C-peptide.

Answer 3

Insulinoma - a Pancreatic neuroendocrine tumors. Relatively benign because removed when discovered.

Question 4

Patient presents with mild diabetes, necrotizing, migratory, erythematous rash, anemia, diarrhea, and deep venous thrombosis.

Plasma glucagon is highly elevated.

Answer 4

Glucagonoma, a ancreatic neuroendocrine tumor.

Question 5

Patient presents with mild diabetes, gallstones, steatorrhea, hypochlorhydria, anemia, and weight loss. Blood levels of insulin and glucagon are low.

Answer 5

Somatostatinoma - a pancreatic neuroendocrine tumor.

Question 6

Patient presnts with intractable gastric hypersecretion and severe peptic ulceration of the duodenum and jejunum despite PPI usage. CT shows a pancreatic mass.

Answer 6

Pancreatic gastrinoma - pancreatic neuroendocrine tumor. Made of G cells which produce gastrin.

Zollinger-Ellison syndrome: Intractable gastric hypersecretion, severe peptic ulceration of duodenum and jejunum, and high blood gastrin levels.

Second in frequency to insulinomas, most common functioning tumor in MEN1.

Question 7

A patient presents with explosive and profuse watery diarrhea, hypokalemia, and achlorhydria. A large solitary pancreatic mass is found.

Answer 7

VIPoma - pancreatic neuroendocrine tumor.

Vener-Morrison syndrome: Explosive and profuse watery diarrhea, hypokalemia, and achlorhydria.