Multiple Endocrine Neoplasia Type 1 (MEN1): Recognition, Evaluation, and Management

Abstract

SIGNIFICANCE OF THE CLINICAL PROBLEM Multiple endocrine neoplasia type 1 (MEN1) is characterized by the occurrence of parathyroid, pancreatic islet, and anterior pituitary tumors (Table 1) (1–6). Some patients may also develop carcinoid tumors, adrenocortical tumors, facial angiofibromas, collagenomas, and lipomas (1–6). MEN1 is an autosomal-dominant disorder, due to mutations of the tumor suppressor gene MEN1, which encodes a 610 amino acid protein, Menin (1, 7, 8). Thus, the finding of MEN1 in a patient has important implications for family members because firstdegree relatives have a 50% risk of developing the disease and can often be identified by MEN1 mutational analysis (1, 3). Patients with MEN1 have a decreased life expectancy and the outcomes of current treatments, which are generally similar to that for the respective tumors occurring in non-MEN1 patients, are not as successful because of multiple tumors which may be larger, more aggressive, and resistant to treatment, and the concurrence of metastases (1, 9–12). The prognosis for patients with MEN1 might be improved by presymptomatic tumor detection and undertaking treatment specific for MEN1 tumors (12).