Answer: C
This patient presents with a constellation of findings that strongly support a diagnosis of Multiple Endocrine Neoplasia type 2B (MEN2B). His large eyelid lesion is characteristic of a mucosal neuroma, which frequently arises at the eyelid margins and conjunctiva in MEN2B. Additional key features of MEN2B include prominent corneal nerves, yellow-pink lesions near the lower eyelid (also consistent with neuromas), thickened lips with mucosal nodules, and a marfanoid body habitus. Other ocular findings can include keratitis sicca and thickened upper and lower lids.
MEN2B is a hereditary disorder characterized by a high risk for medullary thyroid cancer, pheochromocytoma, and mucosal neuromas, along with marfanoid body habitus. The most life-threatening manifestation of this syndrome is medullary thyroid carcinoma, which is often detected through elevated serum calcitonin and thyroid nodules, making choice C the correct answer.
Choice A (Retinal angiomas and cerebellar hemangioblastomas) is associated with Von Hippel–Lindau (VHL) disease, a genetic syndrome involving vascular tumors in the retina, brain, and other organs. VHL does not typically feature mucosal neuromas, corneal nerve thickening, or marfanoid habitus.
Choice B (Café-au-lait spots and Lisch nodules) describes features of Neurofibromatosis type 1 (NF1), which presents with neurofibromas (not mucosal neuromas), iris hamartomas (Lisch nodules), and skin findings. NF1 does not usually present with corneal nerve thickening, lip neuromas, or a marfanoid habitus.
Choice D (Hypopigmented ash-leaf spots and cortical tubers) is associated with Tuberous Sclerosis Complex (TSC), which presents with cutaneous findings (like ash-leaf spots, shagreen patches), neurologic symptoms (seizures), and brain lesions (cortical tubers). It lacks the mucosal neuromas and thyroid malignancy risks seen in MEN2B.
Source: https://eyerounds.org/cases/230-men2b.htm#gsc.tab=0
