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What is Which of the following occurs in long standing goitre: and explain in detail?
Ans: b (Follicular carcinoma) Ref: Hailey, p. 785Follicular Ca is the most common thyroid malignancy from endemic areas. Follicular adenoma and carcinoma can be differetiated only from vascular and capsular invasion by histology.Overall the most common thyroid malignancy-PapillaryPsammoma bodies are seen in-PapillaryDystrophic calcification is seen in-PapillaryOrphan annie nucleus is seen in-PapillaryLeast malignant-PapillaryMC thyroid malignancy after irradiation-PapillaryMC thyroid malignancy in longstanding MNG-FollicularMC thyroid malignancy in endemic areas-FollicularCancer derived from C cells of thyroid-MedullaryMalignancy associated with MEN syndrome-MedullaryMalignancy associated with amyloidosis-MedullaryMost malignant thyroid Ca. AnaplasticOccult carcinoma The term occult carcinoma is applied to all papillary Ca < 1.5 cm diameterIt has good prognosis