RET and pheochromocytoma: MEN2A is characterized by the occurrence of PHPT in association with medullary thyroid carcinoma (MTC) and pheochromocytoma (Table 3).(122, 123) PHPT manifests with a lower penetrance and usually later than MTC and pheochromocytoma.(124) Gain‐of‐function RET mutations cause MEN2A (Table 3) and are readily detected by DNA testing, but the diagnosis is generally apparent by the time PHPT presents.(123, 124, 125)