All of the following are features of MEN IIb, except -
High-Yield Explanation
MEN 2A is characterised by Medullary Thyroid Carcinoma (90%), Pheochromocytoma (>50%) and Parathyroid adenoma (10-25%).MEN 2B (also known as MEN 3) is characterised by MTC (>90%), Pheochromocytoma (>50%) and associated abnormalities (40-50%) - mucosal neuromas, marfanoid habitus, medullated corneal nerve fibres, megacolon. Reference : page 2336 Harrison's Principles of Internal Medicine 19th edition