Multiple endocrine neoplasia type 2 classification

Classification
The two major types of multiple endocrine neoplasia type 1 and type 2, are often confused because they have similar names. These types are distinguished by the genes involved, the hormones that are affected, and their characteristic signs and symptoms. They are also very different in their options for cancer prevention and treatment. Multiple endocrine neoplasia type 2 can be further divided into three subtypes: type 2A, type 2B, and familial medullary thyroid carcinoma (FMTC). These subtypes differ in their characteristic signs and symptoms and risk of specific tumors, but are relatively consistent within any one family.

MEN IIa is characterized by the presence of Medullary thyroid carcinoma, pheochromocytoma, and parathyroid hyperplasia or tumor.

MEN IIb is characterized by the presence of pheochromocytoma, mucocutaneous neuroma, and medullary thyroid cancer.