The BRAF(V600E) mutation is associated with malignant ultrasonographic features in thyroid nodules

Context Several ultrasonographic (US) features of thyroid nodules have been reported to predict malignancy. The BRAF^V600E mutation is a useful diagnostic marker for differentiating papillary thyroid carcinoma from benign thyroid nodules, especially in BRAF^V600E‐prevalent populations such as in Korea. Objective To evaluate the association of BRAF^V600E mutation with US features of thyroid nodules in predicting the malignancy of thyroid nodules in Korean patients. Design A total of 991 thyroid nodules from 823 patients in fine‐needle aspiration biopsy (FNAB) specimens were investigated. The relationship between US features and the presence of BRAF^V600E mutation by pyrosequencing method was prospectively analysed. Results The BRAF^V600E mutation was associated with the following US features: solid composition [odds ratio (OR) 20·338; 95% confidence interval (CI): 4·952–83·532; P < 0·001], marked hypoechogenicity (OR 30·744; 95% CI: 15·951–59·255; P < 0·001), irregular margin (OR 9·889; 95% CI: 7·005–13·859; P < 0·001), taller‐than‐wide shape (OR 6·031; 95% CI: 4·343–8·376; P < 0·001) and the presence of microcalcifications (OR 6·664; 95% CI: 4·604–9·648; P < 0·001). The BRAF^V600E mutation with malignant US features in FNAB enhanced the diagnostic accuracy compared with cytologic diagnosis alone (94·3%vs 69·7%). Conclusion The BRAF^V600E mutation is significantly associated with malignant US features, such as solid composition, marked hypoechogenicity, irregular margin, taller‐than‐wide shape and the presence of microcalcifications. The application of BRAF^V600E mutation analysis in US‐guided FNAB can improve the diagnostic accuracy of thyroid nodules.