ESA-SRB-AOTA 2019

Objective:To estimate the BRAFV600E mutation frequency in Chinese patient with papillary thyroid carcinoma (PTC), and the diagnostic value of BRAFV600E mutation status in thyroid nodules with indeterminate TBSRTC categories.

Methods:A total of 4875 consecutive samples for thyroid ultrasound-guided fine-needle aspiration cytology (FNAC) and BRAF^V600Emutation analysis were collected. Among all the cases, 314 underwent thyroidectomy. FNAC was performed for a preoperative diagnosis. ROC of the subject was constructed to evaluate the diagnostic value of these two methods and their combination.

Results:BRAF^V600Emutation in FNAC of thyroid nodules occurred in 2796 samples (57.35%). Of 353 nodule samples from 314 patients with thyroid operation, 333 were pathologically diagnosed as PTC. Of these PTC patients, 292 (87.69%) were found to have BRAF^V600Emutation in their preoperative FNAC. In 175 cytologically indeterminate thyroid nodules, BRAF^V600Emutation identified 88% of PTC. According to ROC data, BRAF^V600Emutation testing had an obviously higher sensitivity (87.69%) and specificity (100.00%) than TBSRTC. Combining BRAF^V600Emutation testing and TBSRTC achieved the largest AUC (0.954). For 41 PTC with a negative BRAF^V600Emutation in preoperative evaluation, the repeated BRAF^V600Emutation testing found out 12 samples with BRAF^V600Emutation. The true BRAF^V600Emutation rate of Chinese PTC patients was 91.29%.

Conclusions:Chinese patients with PTC have a higher frequency of BRAF^V600Emutation. The BRAF^V600Emutation testing affords a high diagnostic value in thyroid nodules with indeterminate cytology.