A 40-year-old man undergoes prophylactic thyroidectomy for MEN2B. In addition to medullary thyroid carcinoma, which of the following is the characteristic feature that distinguishes MEN2B from MEN2A?
- A Mucosal neuromas and marfanoid habitus ✓
- B Cutaneous lichen amyloidosis
- C Primary hyperparathyroidism
- D Pheochromocytoma
Correct answer: A. Mucosal neuromas and marfanoid habitus
Explanation
MEN2B is characterized by medullary thyroid carcinoma, pheochromocytoma, and distinctive features including mucosal neuromas (lips, tongue, conjunctiva), intestinal ganglioneuromatosis, and marfanoid body habitus. Primary hyperparathyroidism is seen in MEN2C. Cutaneous lichen amyloidosis is associated with specific RET mutations in MEN2C. Pheochromocytoma occurs in both.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.