Endocrine tumors Flashcards
MEN1
Pituitary, pancreatic (e.g. ZES, insulinoma), parathyroid hyperplasia
MEN2A
Medullary thyroid cancer, pheochromocytoma, parathyroid hyperplasia
MEN2B
Medullary thyroid cancer, pheochromocytoma, mucosal neuromas, Marfanoid habitus
Insulinoma
Assoc with MEN1, causes hypoglycemia. Lab results: hypoglycemia w/ high insulin, high c-peptide, high proinsulin
Labs values in surreptitious insulin use
Hypoglycemia w/ high insulin, low c-peptide, low proinsulin
Lab values in sulfonylurea overuse
Hypoglycemia w/ high insulin, high c-peptide, normal proinsulin
Zollinger-Ellison syndrome (gastrinoma) features
Tumor of pancreatic islet cells, secreting gastrin –> gastric acid hypersecretion –> ulcers. 60% are malignant, 20% are assoc with MEN1
How does ZES cause diarrhea?
Acid inactivates pancreatic enzymes –> steatorrhea
Diagnosis of ZES
Secretin injection –> will fail to inhibit gastin levels in ZES
Serum gastrin levels > 1000 diagnostic
Glucagonoma (pancreatic tumor) features
DVT (hyperviscous blood)
Dermatitis: necrotizing migratory erythema
Diabetes (mild-hyperglycemia)
Depression
Somatostatinoma (pancreatic tumor) features
Rare malignant tumor with poor prognosis
Gallstones, diabetes, steatorrhea
Pathophys of somatostatinoma features
The generalized inhibition of gastrointestinal hormones results in restriction of gallbladder contractility, pancreatic exocrine function, and intestinal secretion and motility
VIPoma (pancreatic tumor) features
Watery diarrhea, achlorhydria (VIP inhibits gastric acid secretion), hyperglycemia, hypercalcemia
Can be a part of MEN1
How does VIPoma cause diarrhea?
VIP is a potent stimulator of gut cyclic adenosine monophosphate (cAMP) production, which leads to massive secretion of water and electrolytes (mainly potassium).
