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: Pathology
[{'content': 'The feature that differentiates a follicular carcinoma from a follicular adenoma of thyroid is - \nSelect and explain. \nA. Nuclear pleomorphism, B. Huhle cell change, C. Capsular invasion, D. Absence of colloid', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Capsular invasion Differentiating feature of follicular adenoma from follicular carcinoma. o The hallmark of all follicular adenomas is the presence of on intact ,wall-formed capsule encircling the tumor. o Careful evaluation of the integrity of the capsule is therefore critical in distinguishing follicular adenomas from follicular carcinomas which demonstrate capsular and /or vascular invasion . o Huhle cells are seen both in follicular adenomas and follicular carcinoma (Note -Huhle cells are also seen in hashimoto thyroiditis) Differentiation of follicular adenoma from multinodular goiter Multinodular goiter lacks well formed capsule while follicular adenoma has well formed capsule. o Multinodular goiter produce less compression of the adjacent thyroid parenchyma ,while follicular adenoma comresses the adjacent thyroid. o In multinodular goiter the involved and uninvolved (normal ) thyroid have similar growth pattern , on the other hand growth pattern within the adenoma is distinct from the adjacent non- neoplastic thyroid.", 'role': 'assistant'}]