Multiple endocrine neoplasia type 2

A rare multiple endocrine neoplasia (MEN) syndrome that is principally characterized by the association of medullary thyroid carcinoma (MTC) with other endocrine tumors. The variant MEN 2A is defined by MTC associated with pheochromocytoma and/or primary hyperparathyroidism (MEN2A); the variant MEN 2B is defined as an aggressive form of MTC in association with pheochromocytoma but without primary hyperparathyroidism.