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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
FNAC is useful in all the following types of thyroid carcinoma except
assistant
The correct answer is  Although FNAC is impoant in the workup of thyroid nodules, it is of limited value in the preoperative diagnosis of follicular thyroid cancer. Diagnosis of follicular thyroid cancer requires demonstration of cellular invasion of the capsule or vascular or lymphatic channels. These structural characteristics cannot be determined with FNAC. Source : Sabiston 20th edition Pg: 905