Multiple endocrine neoplasia

The term multiple endocrine neoplasia (MEN) encompasses several distinct syndromes featuring tumors of endocrine glands, each with its own characteristic pattern. In some cases, the tumors are malignant, in others, benign. Benign or malignant tumors of nonendocrine tissues occur as components of some of these tumor syndromes.

MEN syndromes are inherited as autosomal dominant disorders.

Terminology
The older names "multiple endocrine adenomas", or "multiple endocrine adenomatosis" (MEA) have been replaced by the current terminology.

The term multiple endocrine neoplasia is used when two or more endocrine tumor types, known to occur as a part of one of the defined MEN syndromes, occurs in a single patient and there is evidence for either a causative mutation or hereditary transmission. The presence of two or more tumor types in a single patient does not automatically designate that individual as having MEN because there is a small statistical chance that development of two "sporadic" tumors that occur in one of the MEN syndromes could occur by chance.

The term "multiple endocrine neoplasia" was introduced in 1968, but descriptions of the condition date back to 1903.

Related conditions
Although not officially categorized as multiple endocrine neoplasia syndromes, Von Hippel-Lindau disease and Carney complex are two other autosomal dominant endocrine tumor syndromes with features that overlap the clinical features of the MEN syndromes. Although not transmitted in the germline, McCune-Albright syndrome is a genetic syndrome characterized by endocrine neoplastic features involving endocrine glands that overlap with those involved in MEN1 or MEN2.

Comparison
(Blanks indicate that data are not yet available.)

MEN 2B is sometimes known as MEN 3 and the designation varies by institution (c.f. www.ClinicalReview.com). Although a variety of eponyms have been proposed for MEN2B (e.g. Williams-Pollock syndrome, Gorlin-Vickers syndrome, and Wagenmann-Froboese syndrome), none ever gained sufficient traction to merit continued use and, indeed, are all but abandoned in the medical literature. Another early report was Schimke et al in 1968.

OMIM also includes a fourth form of multiple endocrine neoplasia ("MEN4"), associated with CDKN1B. The presentation is believed to overlap that of MEN1 and MEN2.