Predicting factors of lateral neck lymph node metastases in patients with papillary thyroid microcarcinoma

The incidence of papillary thyroid microcarcinoma (PTMC) has increased dramatically in recent years. Compared with central lymph node metastases, lateral neck lymph node (LNLN) metastases in patients with PTMC were less studied. The aim of the present study is to analyze the predicting factors associated with LNLN metastases in patients with PTMC. A total of 3514 patients underwent thyroid surgery at our hospital from January 2017 to December 2017, and 936 patients with PTMC were selected and assessed retrospectively. They were further divided into 2 groups based on whether LNLN metastases existed or not. The relationship between LNLN metastases and clinicopathologic features of PTMC was analyzed. LNLN metastases were confirmed in 126 patients. Univariate and multivariate analyses found 5 independent factors associated with LNLN metastases. They were tumor size (>= 0.7cm) [odds ratio (OR)=1.960, 95% confidence interval (95% CI) 1.227-3.131; P=.005], multifocality (OR=2.254, 95% CI 1.398-3.634; P=.001), tumor location (upper portion) (OR= 6.312, 95% CI 3.853-10.340; P<.001), thyroid cancer family history (OR=7.727, 95% CI 2.227-26.818; P=.001), and central lymph node metastases (OR=11.810, 95% CI 6.547-21.302; P<.001). The findings of our study indicated that LNLN metastases were not rare in patients with PTMC, and tumor size (>= 0.7 cm), multifocality, tumor location (upper portion), thyroid cancer family history, and central lymph node metastases were independent factors for LNLN metastases. In order to perform individualized management, LNLN should be meticulously evaluated when these features are detected.