MULTIPLE ENDOCRINE NEOPLASIA SYNDROMES
Multiple endocrine neoplasia (MEN) syndromes are autosomal dominant conditions with incomplete penetrance that are characterized by hyperplasia and tumors of endocrine glands occurring at a young age.
• MEN 1 (Werner syndrome) features tumors of the pituitary gland, parathy-roids, and pancreas.
• Associated with peptic ulcers and Zollinger-Ellison syndrome
Affected gene is MEN1, a tumor suppressor gene which encodes a nuclear protein called menin
• MEN 2A (Sipple syndrome) features medullary carcinoma of the thyroid, pheo-chromocytoma, and parathyroid hyperplasia or adenoma.
Mutation of RET proto-oncogene
• MEN 2B features medullary carcinoma of the thyroid, pheochromocytoma, and mucocutaneous neuromas.
• Mutation of RET proto-oncogene