The combination of BRAF^V600E mutation and Chinese Thyroid Imaging Reporting and Data System is helpful in the management of AUS/FLUS thyroid nodules

Purpose: To explore the utility of the BRAF^V600E mutation in combination with the Chinese Thyroid Imaging Reporting and Data System (C-TIRADS) in the management of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) thyroid nodule (TN).

Methods: 138 AUS/FLUS TNs in 129 patients were included. Each TN underwent preoperative BRAF^V600E mutation analysis and was classified using the C-TIRADS. Histopathologic diagnosis served as reference standard.

Results: 46 benign TNs and 92 malignant TNs were identified. The C-TIRADS 4C and 5 (OR = 10.409, P = 0.000), BRAF^V600E mutation (OR = 36.493, P = 0.000) were independent predictors of malignant nodules. There were significant differences in malignancy rate among the different C-TIRADS TNs (P = 0.000), and these TNs with higher C-TIRADS were associated with increased malignancy rate (P for trend = 0.000). The rate of the nodule with BRAF^V600E mutation increased with the increase of C-TIRADS (P for trend = 0.001). For AUS/FLUS TNs without BRAF^V600E mutation, the malignancy rates of the C-TIRADS 3, 4A, 4B, 4C, and 5 were 0%, 21.4%, 20.8%, 70.8%, and 100%, respectively (P = 0.000), and the malignancy rate increased from C-TIRADS 3 to C-TIRADS 5 (P for trend = 0.000). C-TIRADS and BRAF^V600E mutation had similar diagnostic efficacy (P > 0.05), and the sensitivity, negative predictive value, and accuracy of the combination were significantly higher than BRAF^V600E gene or C-TIRADS alone (P < 0.05).

Conclusions: C-TIRADS can effectively provide risk stratification for AUS/FLUS nodules. The combination is helpful in selecting appropriate management for AUS/FLUS patients.