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What is Fine needle aspiration cytology (FNAC) is not enough to diagnose: and explain in detail?
Ans: B. Follicular carcinoma of the thyroid(Ref: Robbin's 9/e p1094, 8/e p1123).FNAC:Not enough to diagnose follicular carcinoma.Since follicular carcinoma is differentiated from follicular adenoma based on capsular invasion & vascular invasion (not diagnosed by FNAC).Limitations of FNAC in Thyroid Diseases:Not able to distinguish follicular adenoma from follicular carcinoma.Not able to distinguish Huhle cell adenoma from Huhle cell carcinomaUseless in Reidel's thyroiditis (Biopsy is preferred).FNAC is less reliable in patients who have a history of head & neck irradiation or family history of thyroid cancer due to the higher likelihood of multifocal lesions & occult cancer.