[Diagnostic values of BRAF(V600E) mutation analysis and Bethesda system for reporting thyroid cytopathology in thyroid nodules with TIRADS 4 and 5].

Objective: To evaluate the diagnostic efficacies of BRAF(V600E) testing and Bethesda system for reporting thyroid cytopathology (BSRTC) in thyroid nodules with thyroid imaging reporting and data system (TIRADS) category 4 and 5. Methods: A total of 187 thyroid nodules in 187 patients underwent the examinations of ultrasound-guided fine needle aspiration cytology (FNAC) and BRAF(V600E) mutation were analyzed retrospectively. Receive operating characteristic (ROC) curve was used to investigate the diagnostic values of both methods and the clinical application of BRAF(V600E) combined with BSRTC was evaluated. SPSS17.0 software was used to analyze the data. Results: Among 187 thyroid nodules, 123 were malignant nodules confirmed with histopathological examination and 64 benign nodules determined by FNAC, histopathological examination, or long-term follow-up. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of BRAF(V600E) test were better than those of BSRTC [69.1%, 98.4%, 98.8%, 62.4%(χ(2)=77.3, P =0.000) vs 62.6%, 93.8%, 95.1%, 56.6%(χ(2)=54.4, P =0.000)]. While the sensitivity, specificity, PPV and NPV of the combined test of BRAF(V600E) and BSRTC for diagnosis of malignant thyroid nodules were 87.8%, 92.2%, 95.6%, 79.7%(χ(2)=112.6, P =0.000), respectively. The area under the ROC curve for the combined test was higher than that for each of tests (0.900 vs 0.858 or 0.838). Conclusions: The combined test of BRAF(V600E) mutation and BSRTC has a higher diagnostic efficacy for malignant thyroid nodules compared with BRAF(V600E) mutation or BSRTC alone.