Multiple Endocrine Neoplasia Flashcards
(28 cards)
What are multiple endocrine neoplasia (MEN) syndromes?
3 well characterized, inherited pluriglandular disorders in which several endocrine glands simultaneously undergo neoplasic transformation and become hyperfunctional.
How are MEN syndromes genetically transmitted?
autosomal dominant
What are the types of MEN syndromes?
MEN-1, MEN-2A, and MEN-2B
What is MEN-1?
hyperplasia or neoplastic transformation of the parathyroid glands, pancreatic islets, and pituitary
What is MEN-2A?
hyperplasia or neoplastic transformation of the thyroid parafollicular cells (medullary thyroid carcinoma [MTC]), parathyroid glands, and adrenal medulla (pheochromocytoma)
What is MEN-2B?
hyperplasia or neoplastic transformation of the thyroid parafollicular cells (MTC) and adrenal medulla (pheochromocytoma) with concomitant development of mucosal neuromas
What is Wermer syndrome?
another name for MEN-1
What is the prevalence of MEN syndromes?
MEN1 - 2-20/100,000
MEN2- less common
type 2A - more common form
type 2B - 5% of all type 2
What cells do MEN tumors arise from?
amine precursor uptake and decarboxylation (APUD) group
What tumors are associated with MEN1?
parathyroid adenoma 95%
pancreatic endocrine tumors
pituitary adenoma
carcinoid tumors
What tumors are associated with MEN2A?
medullary thyroid carcinoma 100%
bilateral phaeochromocytoma
parathyroid adenoma
What tumors are associated with MEN2B?
neuromas 100%
medullary carcinoma of the thyroid 100%
phaeochromocytoma
Which syndrome is associated with ZE syndrome?
MEN1
What is MEN1 caused by?
mutation in MEN1 gene –> menin protein (tumor supressor)
What are the locations of MEN1 carcinoid tumors?
men: thymus
women: bronchial carcinoids
What are the diagnosis requirements for MEN1?
- clinical: 2 or more MEN1 associated tumors
- familial: pt with one MEN1 associated tumor and a 1st degree relative with MEN1
- genetic: asymptomatic carrier of MEN1 mutation
What is the most frequently involved organ of MEN1?
parathyroid gland 95%
What is usually the first manifestation of MEN1?
hyperparathyroidism from hyperplasia of all 4 glands
What is the second most common manifestation of MEN1?
neoplastic transformation of pancreatic islet cells
- gastrinoma
- insulinoma
- glucagonomas, somatostatinomas, and vasoactive intestinal polypeptide secreting tumors (VIPomas)
What do most pituitary tumors in MEN1 secrete?
-symptoms
prolactin
- galactorrhea
- amenorrhea
- impotence
What is treatment for MEN1?
- surgical resection of hyperplastic parathyroid tissue
- surgical resection of pituitary adenomas or pharmacological management (bromocriptine for prolactinomas and octreotide for acromegaly)
- subtotal pancreatectomy
MEN2 cause
activating mutation of the RET protooncogene –> receptor tyrosine kinase for cellular development
What is the most common sign of MEN2? Another sign?
malignant transformation of parafollicular c cells = medullary thyroid carcinoma (MTC)
50% develop pheochromocytoma
Which is more severe? MEN 2A or 2B?
2B - avg age of death 30 years
2A -avg age of death 60 years
