Diagnostic value of BRAF(V600E) mutation analysis of thyroid nodules according to ultrasonographic features and the time of aspiration.

Abstract

BACKGROUND: We investigated the diagnostic value of the BRAF(V600E) mutation of thyroid nodules according to ultrasonography (US) features and the time of BRAF(V600E) mutation analysis.

METHODS: A total of 304 nodules in 295 patients (mean age, 49.4 years) were included. Thyroid nodules were classified as suspicious or probably benign on US. Group 1 (n = 168) included nodules with BRAF(V600E) mutation analysis at the time of the initial US-guided fine needle aspiration biopsy (US-FNAB) and group 2 (n = 136) included nodules with analysis at the time of the repeat US-FNAB. The frequency of malignancy and the BRAF(V600E) mutation were compared between suspicious and probably benign nodules on US and between groups 1 and 2.

RESULTS: Of 304 nodules, 113 were malignant and 59 (52.2%) had the BRAF(V600E) mutation. Also, 58 of 196 nodules suspicious on US (29.6%) had the BRAF(V600E) mutation, whereas 1 of 108 (0.9%) probably benign nodules had the BRAF(V600E) mutation (P value <.0001). The BRAF(V600E) mutation was more frequently found in nodules suspicious on US than those probably benign in both groups 1 and 2 (P value <.0001 and .0058, respectively). Preoperative detection of the BRAF(V600E) mutation led surgeons to perform surgery in 5.8% of 103 nodules with benign and nondiagnostic results on cytology in group 1 and 1% of 98 nodules in group 2 without treatment delay.

CONCLUSIONS: The BRAF(V600E) mutation analysis was a useful adjunctive diagnostic tool, especially in nodules suspicious on US, and was more effective if performed at the time of the initial US-FNAB.