endocrine and metabolic disorders
Multiple Endocrine Neoplasia, Type 1 (MEN 1)
Introduction
Multiple endocrine neoplasia, type 1 (MEN 1) is an autosomal dominant syndrome characterized by hyperplasia or adenomas of the parathyroid glands, pancreatic islet cell tumors (also known as pancreatic neuroendocrine tumors), and/or pituitary gland tumors. Duodenal gastrinomas, carcinoid tumors of the foregut, benign adrenal adenomas, and lipomas also occur. Hyperparathyroidism and asymptomatic hypercalcemia commonly occur. Family members are offered genetic screening. Diagnosis is by hormonal and imaging tests. Tumors are removed surgically if they cause symptoms or for suspected malignancy based on size criteria. (See also Overview of Multiple Endocrine Neoplasias (MEN) .) gene that encodes the nuclear protein menin; > 500 mutations of this gene have been identified. The exact function of menin is unknown, but it appears to have tumor-suppressing effects. Some mutations are thought to be associated with a higher rate of Overview of Pancreatic Endocrine Tumors development, a higher rate of distant metastases, and more aggressive disease ( About 40% of MEN 1 cases involve tumors of all 3 affected glands: Parathyroids Pancreas Pituitary Almost any combination of the tumors and symptom complexes outlined below is possible. A patient with a MEN 1 gene mutation and one of the MEN 1 tumors is at risk of developing any of the other tumors later on. Age at onset ranges from 4 to 81 years, but peak incidence occurs in the 20s to 40s. Men and women are equally affected. 