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

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.