Multiple Endocrine Neoplasia Type 1

Synonyms

MEN1; Multiple endocrine adenopathy type 1; Wermer syndrome; WMEN1

Definition

Multiple endocrine neoplasia type 1 (MEN1) is characterized by the combined occurrence of tumors of the parathyroids, pancreas, and pituitary, and is inherited as an autosomal dominant trait.

Characteristics

Multiple endocrine neoplasia type 1 is characterized by the combined occurrence of tumors (Table 1) of the parathyroid glands, pancreatic islet cells, and anterior pituitary gland. Some patients may also develop adrenal cortical tumors, carcinoid tumors, facial angiofibromas, collagenomas, and lipomas. MEN1 is inherited as an autosomal dominant disorder with a high degree of penetrance, such that >95% of patients develop clinical manifestations of the disorder by the fifth decade. The earliest age at which manifestations of MEN1 may occur has been reported to be 5 years. Parathyroid tumors, which lead to hypercalcemia (Table 1), are the most common feature of MEN1 and occur in about 95% of...