Endocrine Abstracts

Multiple endocrine neoplasia type 2 (MEN 2) is an autosomal dominant hereditary cancer syndrome caused by missense gain-of-function mutations of the RET proto-oncogene, encoding a receptor tyrosine kinase, on chromosome 10. It has a strong penetrance of medullary thyroid carcinoma (MTC) and can be associated with bilateral pheochromocytoma and primary hyperparathyroidism. MEN 2 is divided into three varieties depending on clinical features: MEN 2A, MEN2B and FMTC (familial MTC). The specific RET mutation may suggest a predilection toward a particular phenotype (MEN 2A, MEN 2B and FMTC) and clinical course of the MTC, with strong genotype–phenotype correlations. Offering RET testing is best practice for the clinical management of patients at- risk of MEN 2, and MEN 2 has become a classic model for the integration of molecular medicine into patient care. Recommendations on the timing of prophylactic thyroidectomy and extent of surgery are based on classification of RET mutations into risk levels according to genotype–phenotype correlations. By earlier identification of patients with hereditary MTC, the presentation changed from clinical tumours to preclinical disease resulting in a high cure rate of affected patients with much better prognosis.

Declaration of interest: The author declares that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.