MULTIPLE ENDOCRINE DISORDERS

MEN 1 [pituitary tumour, parathyroid hyperplasia/tumour, pancreatic tumours (most commonly gastrinoma / insulinoma)]. Also known as Wermer’s syndrome.

Hyperparathyroidism is the most common and earliest feature of MEN1 ( 80-95%). Usually all four glands become hyperplastic.

Neoplastic transformation of pancreatic islets is the second most common manifestation of MEN1 (80%). Gastrinomas are the most common (presenting with peptic ulcer disease and diarrhoea. Insulinomas are the second most common. Pituitary tumours occur in 50-70% of cases.

Familial multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant disorder. The MEN1 gene on chromosome 11q13 has been cloned and mutations identified. The gene emcodes a protein called menin which acts as a tumour suppressor gene.

MEN 2

MEN 2a is associated with medullary thyroid carcinoma (MTC), parathyroid tumours

(10-20%) and pheochromocytoma (20-50%).

MEN 2b is associated with presentation of medullary thyroid carcinoma, parathyroid tumours and pheochromocytoma + ganglioneuromatosis (pathognomonic), and marfanoid habitus.