Risk factors for central lymph node metastasis in papillary thyroid microcarcinoma - a retrospective study of 1433 cases from a single center.

The purpose of this retrospective study was to evaluate the clinicopathological features of papillary thyroid microcarcinoma (PTMC) and the lymph node metastasis of PTMC. We retrospectively reviewed a total of 1433 patients with PTMC. The analysis data including demographics, tumor size, multifocality, bilateral, invasion capsule and Hashimoto's thyroiditis were collected from XinJiang, China. Univariate and multivariate analyses were performed to identify the clinicopathologic predictors of central lymph node metastasis: male gender [odds ratio (OR) = 2.358, p < 0.001], age ≤ 45 years (OR = 2.302, p 6.5 mm (OR = 2.388, p < 0.001), adjacent or invasion capsule (OR = 1.750, p = 0.002), Hashimoto's thyroiditis (OR = 0.501, p < 0.001). The optimal critical value of the number of dissected lymph nodes was found to be 8.5 using ROC analysis, with a sensitivity and specificity of 41.8% and 75.5%, respectively. This study suggests that evaluation of nodal metastasis is required to guide the surgical treatment of PTMC patients.