This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Fine needle aspiration cytology (FNAC) is not enough to diagnose: 
Select and explain. 
A. Papillary carcinoma of thyroid, B. Follicular carcinoma of thyroid, C. Carcinoma breast, D. Adenocarcinoma lung
B: Follicular carcinoma of thyroid
Answer: B: Follicular carcinoma of thyroid 
Explanation: 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.