Clinical significance of BRAFV600E and TERT promoter mutation in papillary thyroid microcarcinoma

Objective The objective of this study was to analyze the correlation between BRAFand TERT promoter mutations and papillary thyroid microcarcinoma (PTMC) risk factors, and their importance in the risk assessment of papillary thyroid microcarcinoma.Methods This study retrospectively analyzed 107 cases of PTMC, which were diagnosed after the surgery in the department of head and neck surgery in Gansu Province Tumor Hospital from October 2014to June 2016. The mutations of BRAFVand TERT promoter were detected by PCR direct sequencing.We analyzed the data usingχ~2 test and binary Logistic regression analysis.Results Among 107 patients with PTMC, the BRAFVand TERT promoter mutation rates were 68.2%and 11.2%, respectively. Single factor analysis showed that there was a significant difference between the presence of membrane invasion, lymph node metastasis, and BRAFVmutations (P<0.01). The age,gender, thyroid capsular invasion, poor pathologic subtype, and lymph node metastasis of patients, was significantly associated with the TERT promoter mutation (P<0.05) and the coexistence of the BRAFand TERT promotor mutations; although, there was a difference between the association of these factors with the TERT promoter mutation and the association of these factors with the coexistence of the BRAFand TERT promotor mutations. The multifactorial analysis showed that the factors closely related to the BRAFVmutation included capsular invasion (P=0.012) and lymph node metastasis (P=0.000). The following factors were closely associated with the TERT promoter mutant:male (P=0.004), aged <45 years(P=0.026), capsular invasion (P=0.004), pathological subtype (P=0.030), and lymph node metastasis (P=0.043). The following factors were closely related to the simultaneous mutation of BRAFVand TERT:male (P=0.022), capsular invasion (P=0.023), poor pathological subtype (P=0.041), and lymph node metastasis (P=0.030).Conclusion The risk of recurrence increases significantly when mutations in BRAFVand TERT promoters occur simultaneously in PTMC and may have adverse outcomes. Combined detection of BRAFVand TERT promoter mutations is of great value in risk assessment of PTMC.