Surgical Results of Thyroid Nodules according to a Management Guideline Based on the BRAFV600E Mutation Status

Abstract

Context: In Korea, where PTC comprises about 90–95% of the reported thyroid cancers, the prevalence of BRAFV600E mutation in papillary thyroid carcinoma (PTC) is above 80%. Objective: We analyzed the surgical result according to a management guideline based on the BRAFV600E mutation status of thyroid nodules. Design: A total of 865 thyroid nodules were prospectively analyzed for their cytology and BRAFV600E mutation status by pyrosequencing. For the patients who had a diagnosis of atypical cells of undetermined significance (ACUS), we recommended surgery when there was positivity for BRAFV600E mutation or the nodules were clinically suspicious. Results: Among 865 cases, 504, 141, 54, 140, 10, and 16 were diagnosed as benign, ACUS, suspicious for malignancy, malignant, suspicious for follicular neoplasm, and nondiagnostic, respectively. None of the 504 benign, 45 (31.9%) of the 141 ACUS, 46 (85.2%) of the 54 suspicious for malignancy, 129 (92.1%) of the 140 malignant, and one (10%) of the 10 suspicious for follicular neoplasm cases showed BRAFV600E mutation. Surgery was recommended to all 45 patients with BRAFV600E mutation-positive ACUS nodules; among them, 30 patients underwent surgery, 29 had PTC, and one had nodular hyperplasia. All the patients diagnosed as suspicious for malignancy or malignant were advised to undergo an operation, and they turned out to have PTCs regardless of their BRAFV600E mutation status. Conclusions: We found that performing BRAFV600E mutation analysis on the fine-needle aspiration biopsy specimens was of great help to make a therapeutic decision for thyroid nodules when the fine-needle aspiration biopsy results were equivocal.