Multiple endocrine neoplasia type 1 (MEN 1) revisited.

Multiple endocrine neoplasia type 1 (MEN 1) is an inherited disease of the neuroendocrine cell system affecting primarily the parathyroids, pancreas, duodenum and the anterior pituitary. The pancreatic and duodenal tumours may metastasize, but generally have a low malignant potential. The diagnosis of MEN 1 is usually made in the second decade of life and based on the involvement of at least two organs and a family history. The recent discovery of the MEN 1 locus on the centromeric region of the long arm of chromosome 11 may become a further diagnostic criterion. The use of flanking DNA markers permits presymptomatic testing for MEN 1 in affected families.