2-10-16-Multiple Endocrine Neoplasia Syndromes (Lopez) Flashcards
What is the most prevalent form of MEN?
Men1
MEN tumors arise from the ___ group of cells, which constitute the diffuse system of neuroendocrine cells distributed throughout the body
Amine Precursor Uptake Decarboxylation (APUD)
The APUD acronym denotes the capacity of these cells to synthesize and/or secrete biogenic amines formed through the activity of the enzyme ___
L-DOPA decarboxylase
What types of tumors are associated with MEN1?
Parathyroid adenoma (95%) Pancreatic endocrine tumors (50%) Pituitary adenomas (40%) Carcinoid tumors (30%)
What types of tumors are associated with MEN2A?
Medullary thyroid carcinoma (100%) Bilateral pheochromocytoma (50%) Parathyroid adenoma (10%)
What types of tumors are associated with MEN2B?
Medullary thyroid carcinoma (100%)
Neuromas (100%)
Pheochromocytoma (50%)
Marfanoid habitus and mucosal neuromas are characteristic of ___
MEN2B
___ is associated with possible Zollinger-Ellison and various pituitary pathologies such as acromegaly, cushing syndrome, and galactorrhea
MEN1
Wermer syndrome is caused by mutations in the MEN1 gene, which encodes a protein known as Menin. Menin functionally acts as a ____
Tumor suppressor
Mutations in menin causes unregulated cell division that leads to tumor formation
Tumors in the parathyroid, pancreas (endocrine), and pituitary are associated with ___
MEN1 (Wermer syndrome)
What are 3 means of diagnosing MEN1?
Clinical-2 or more MEN1-associated tumors
Familial-Patient with 1 MEN1-associated tumor and a 1st degree relative with MEN1
Genetic-An asymptomatic carrier of MEN1 mutation (no BCHEM manifestations)
___ is usually the 1st manifestation of MEN1
Hyperparathyroidism
___ is the 2nd most common manifestation of MEN1
Neoplastic transformation of the pancreatic islet cells
The most frequent manifestation of MEN1 pancreatic involvement is a ___
___ are the 2nd most common type of functional pancreatic tumor in MEN1
Gastrinoma
Insulinoma
The symptoms of ___ are the 3rd most common manifestation of MEN1
Hyperprolactinemia
MEN1 patients may develop tumor-secreting __ and present with Cushing Syndrome
MEN1 patients may develop tumor-secreting __ and present with Acromegaly
ACTH
GH
What are therapeutic options for MEN1?
Surgical resection of hyperplastic parathyroid tissue
Surgical resection of pituitary adenomas or pharmacological management of pituitary adenomas with BROMOCRIPTINE for prolactinomas and OCTREOTIDE for acromegaly
Subtotal pancreatectomy
MEN type 2 is caused by an activating mutation of the ___ protooncogene
RET
RET codes for rTK that phosphorylates and activates enzymes critical to cell development
The most common sign of MEN2 is malignant transformation of ___ cells
Parafollicular (C cells)=medullary thyroid carcinoma (MCT)
Overall, mortality in ___ is more severe of the MEN type 2
MEN2B
___ consists of neoplastic transformation of parathyroids, thyroid parafollicular C cells, and adrenal medulla
MEN2A (Sipple syndrome)
Pheochromocytomas associated with MEN2A secrete greater amounts of ___ than sporadic pheochromocytomas
Epinephrine
___ is an itchy skin condition that may present in MEN2 cases
Cutaneous lichen amyloidosis–> usually pruritic, scaly, papular, pigmented, and located in the interscapular region or on the extensor surfaces of the extremities.
___ is the association of MTC and pheochromocytoma with multiple mucosal neuromas in an affected individual
MEN2B syndrome
Hyperparathyroidism is not associated with ___
MEN2B
In what MEN syndrome could pheochromocytoma be involved>
MEN 2-Both type 2a and 2b
In a pheochromocytoma, what is the source of excessive catecholamine secretion?
Chromaffin cells of the adrenal medulla
Congenital adrenal hyperplasia can be caused a deficiency in this enzyme: ____
21-beta-hydroxylase
Mutation in which gene is diagnostic for MEN2A?
RET oncogene
Each MEN syndrome is inherited as a __ trait with a high degree of penetrance and variable expressivity
Autosomal dominant
