FNAC is useful in diagnosing all the following EXCEPT

Ans. b (Follicular carcinoma) (Ref. Bailey and Love 25th/pg. 780)FNAC is the investigation of choice in discrete thyroid swellings. Thyroid conditions that may be diagnosed by FNAC include colloid nodules, thyroiditis, papillary carcinoma, medullary carcinoma, anaplastic carcinoma and lymphoma. FNAC cannot distinguish between a benign follicular adenoma and follicular carcinoma, as this distinction is dependent not on cytology but on histological criteria, which include capsular and vascular invasion.Thyroid cancerA. Papillary carcinoma--most common, excellent prognosis, "ground-glass" nuclei, psammoma bodies.B. Follicular carcinoma--good prognosis, uniform follicles, missed on FNAC.C. Medullary carcinoma--from parafollicular "C cells"; produces calcitonin, sheets of cells in amyloid stroma. MEN types II and III.D. Undifferentiated/anaplastic--older patients, very poor prognosis.