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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
All are involved in MEN IIA except:
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The correct answer is  a. Pituitary(Ref: Nelson's 20/e p 2694-2481, Ghai 8/e p 523)In Multiple Endocrine Neoplasia (MEN) IIA, features seen are: "HAPPY", i.e. Hirschsprung disease, Amyloidosis, Pheochromocytoma, Parathyroid hyperplasia/Adenoma and thyroid Carcinoma (Medullary).