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What is Malignancy in a multinodular goiter is most often:- and explain in detail?
Follicular ca: - Seen in iodine deficient areas - M/C malignancy in long standing goiter - M/c malignancy in multinodular goiter Papillary ca: - Seen in iodine sufficient areas - M/C thyroid malignancy Anaplastic ca: - Rare; m/c seen in females - Usually seen in 7th - 8th decade of life Medullary ca: - Arise from Parafollicular C cells - C cells derived from ultimobranchial bodies