Evaluating the accuracy of fine needle aspiration and frozen section based on permanent histology in patients with follicular lesions

Fine needle aspiration (FNA) has led to a decrease in unnecessary surgeries for thyroid nodules. This study was designed to compare diagnostic value of FNA and frozen section methods in the follicular lesions. This is a cross-sectional study based on the medical records of 42 patients who were referred to surgery clinic of Rasool-e-Akram hospital in Tehran with complaint of thyroid nodules. All FNAs were diagnosed as follicular lesions in pathologic evaluation. All the patients underwent thyroid surgery and their frozen section results were also assessed. Finally, diagnostic value of the two tests was compared based on final permanent histologic report. Forty two patients with follicular thyroid nodules diagnosed with FNA were included. During the operation, using frozen sections, diagnosis of papillary carcinoma, non-papillary malignancies, benign lesion and intermediate cytology was made in 13 (31%), 3 (7%), 25 (59.5%), 1 (2.5%) patients, respectively. Results of permanent histology showed that follicular adenoma is the most prevalent lesion which appeared in 25 (59.5%) cases. Papillary and follicular carcinomas were detected in 10 (23.8%) and 4 (9.5%) cases, respectively. Results of the study demonstrate a 73% reduction in second surgery in patients with follicular thyroid lesions based on intraoperative frozen section results.