Predicting factors of central lymph node metastasis and BRAF V600E mutation in Chinese population with papillary thyroid carcinoma

Objective The aim of this study was to evaluate the predictive factors of central lymph node metastasis (CLNM) and BRAF V600E mutation in Chinese patients with papillary thyroid carcinoma (PTC). Methods A total of 943 PTC patients who underwent thyroidectomy from 2014 to 2016 at our hospital were enrolled. Those patients were divided into PTC > 10 mm and papillary thyroid microcarcinoma (PTMC) groups by tumor size. The BRAF V600E mutation was examined by quantitative real-time PCR. Univariate and multivariate analyses were used to examine risk factors associated with CLNM and the BRAF V600E mutation. Results The frequency of CLNM was 53% (505/943). Both univariate and multivariate analyses suggested that the risk factors for CLNM in PTC patients were male, younger age, and larger tumor size ( P < 0.05). Coexistent Hashimoto thyroiditis (HT) was an independent protective factor against CLNM when the tumor was > 10 mm ( P = 0.006). Stratified analysis revealed that male, age ≤ 30 years, and tumor size > 5 mm were independent risk factors for CLNM. The BRAF V600E mutation rate was 85%. Multivariate logistic regression analysis revealed that age ( P < 0.001) and coexistent HT ( P = 0.005) were independent predictive factors of BRAF V600E mutation in PTC patients. Only age was a risk factor for the BRAF V600E mutation when the tumor was > 10 mm ( P = 0.004). In the PTMC group, the BRAF V600E mutation was significantly correlated with tumor size ( P < 0.001) and coexistent HT ( P = 0.03). Stratified analysis revealed that age > 30 years and tumor size > 5 mm were independent predictive factors of BRAF V600E mutation. Furthermore, the incidence of CLNM was significantly higher in BRAF V600E mutation-positive patients ( P = 0.009) when the tumor was ≤ 5 mm. Conclusion The factors male, younger age (≤ 30 years), large tumor size (> 5 mm), and coexistent HT are independent predicative factors for CLNM. The BRAF V600E mutation is associated with both large size and without HT in PTMC patients, age > 30 years in the PTC > 10 mm group. The BRAF V600E mutation was an independent risk factor for CLNM when the tumor was ≤ 5 mm. For optimal management, these features should be comprehensively evaluated to determine the initial surgical approach for PTC patients.