This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': "The neuroendocrine carcinoma arising from parafollicular 'C' cells of thyroid is: \nSelect and explain. \nA. Papillary carcinoma, B. Follicular carcinoma, C. Medullary carcinoma, D. Anaplastic carcinoma", 'role': 'user'}, {'content': 'Answer: C \nExplanation: MEDULLARY CARCINOMA OF THE THYROID (MCT)\nThese tumours arise from parafollicular ‘C’ cells which are\xa0derived from ultimobranchial bodies and not from thyroid\xa0foillicle.\n\nThese tumours present in two different ways.\n\n\nSporadic is common, seen in about 80-90% of cases.\nFamilial variety present as a part of multiple endocrine\xa0neoplasia (MEN).\n\nMEN Type I\n\nPituitary adenoma\nParathyroid adenoma\nPancreatic adenoma\n\nMEN Type IIa\n\nParathyroid adenoma\nPhaeochromocytoma\nMedullary carcinoma of thyroid\n\n\nWhen it is associated with mucocutaneous neuromas\xa0involving lips, tongue, eyelids, it is called Sipple syndrome,\xa0with an occasional marfanoid habitus (MEN type IIb)\nIt has got a characteristic amyloid stroma\xa0\nThese tumours are not TSH-dependent and do not take up\xa0radioactive iodine\xa0\n\nHormones produced by MCT\n\nCalcitonin\xa0\nProstaglandins\nSerotonin (5-HT), ACTH\n\nSpread\n\nBoth by lymphatics and blood, thus, worsening the prognosis.\n\nKey Concept:\nMedullary Carcinoma arises from parafollicular C cells which are derived from ultimobranchial bodies and not from thyroid follicle. The medullary carcinoma produces hormones such as Calcitonin, Prostaglandins and serotonin.\nReference:\xa0 Manipal Manual of Surgery 4th ed page no 348', 'role': 'assistant'}]