multiple endocrine neoplasia type 2B

Multiple Endocrine Neoplasia type 2B (MEN2B) is a rare, inherited disorder characterized by tumors in multiple endocrine glands. It is a subtype of Multiple Endocrine Neoplasia type 2 (MEN2) and accounts for less than 5% of MEN2 cases.1

Pathology of MEN2B

MEN2B primarily involves:
* Medullary thyroid carcinoma: This is nearly always present in patients with MEN2B, occurring in about 95% of cases. It arises from the C cells of the thyroid gland.1
* Pheochromocytomas: Tumors of the adrenal glands that can cause high blood pressure, found in about 50% of patients.1
* Ganglioneuromas: Benign tumors that can occur in the gastrointestinal tract and on the lips, tongue, and lining of the mouth and throat, present in about 95% of patients.1
* Physical appearance: Patients often have a tall, lean body with long extremities.1

Unlike other forms of MEN2, MEN2B typically does not involve hyperparathyroidism. The underlying cause is usually a mutation in the RET proto-oncogene, which leads to constant activation of cell signaling pathways, promoting tumor formation. Early detection and surgical removal of the thyroid gland are crucial, especially in individuals with a known RET mutation, to prevent the development of medullary thyroid carcinoma.12