Multiple endocrine neoplasia classification

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

MEN 2B was known as MEN 3 for a short time in the 1970s, but that term is no longer used. 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 suffiicient 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.

MEN type 1
Type 1 is also known as Wermer's syndrome after Dr Paul Wermer, who described it in 1954: The causative mutation is in the MEN1 gene at 11q13 which encodes a nuclear protein called menin that is believed to act as a tumor suppressor. Most cases of multiple endocrine neoplasia type 1 are inherited in an autosomal dominant pattern.
 * 1) Parathyroid hyperplasia/tumour causing hyperparathyroidism.
 * 2) Pancreatic islet cell tumours causing hypoglycaemia (insulinoma) and Zollinger-Ellison syndrome (gastrinoma).
 * 3) Pituitary adenoma which may cause pituitary hormone excess.

MEN type 2/type 2a
MEN syndrome types 2 and 3 have their basis in molecular genetics. Individuals can be tested for this genetic disorder reliably even when asymptomatic. The mutation is in the RET proto-oncogene. Most cases of multiple endocrine neoplasia types 2 and 3 are inherited in an autosomal dominant pattern.

Type 2 is also known as Sipple syndrome (after the American Dr John H. Sipple, who described it in 1961) and used to be called type 2A:


 * 1) Medullary carcinoma of the thyroid which is associated with increased calcitonin secretion. A test for elevated calcitonin should be done after pentagastrin injection and/or calcium infusion, to ensure that all affected patients are detected.
 * 2) Pheochromocytoma
 * 3) Parathyroid hyperplasia/tumour causing hyperparathyroidism.

MEN type 3/type 2b
This syndrome has no eponym; it was described by Schimke et al in 1968. Originally thought to be a third MEN, then considered a variant of II (especially after linkage to RET was confirmed), it is now considered its own syndrome.
 * 1) Pheochromocytoma
 * 2) Medullary carcinoma of thyroid which is associated with increased calcitonin secretion. A test for elevated calcitonin should be done after pentagastrin injection and/or calcium infusion, to ensure that all affected patients are detected.
 * 3) Mucosal neuromas which are usually situated in the gastrointestinal tract.
 * 4) Marfanoid habitus