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What is All are true about medullary thyroid carcinoma except: and explain in detail?
Answer- B. RadiosensitiveThese are tumours of the parafollicular (C cells) derived from the neural crest.There is a characteristic amyloid stroma.High levels of serum calcitonin and carcinoembryonic antigen are produced medullary tumours.Calcitonin levels fall efter resection and rise again with recurrence making it a valuable tumour marker in the follow up of patients with this disease.Diarrhoea due to 5-hydroxytrptamine or prostaglandins.Tumours are not TSH dependent and do not take up radioactive iodine.