The analysis of clinicopathologic predictors of lymph node metastasis and postoperative recurrence in patients with papillary thyroid microcarcinoma from Guangdong Province, China-a multicenter retrospective study

Purpose: Currently the extent of lymph node dissection (LND) for papillary thyroid microcarcinoma (PTMC) remains controversial. The present study aims to investigate the clinicopathologic predictors of lymph node metastasis (LNM) and prognosis in PTMC patients from Guangdong to enable appropriate treatment and follow-up. Methods: Data including demographics, tumor size, multifocality, extrathyroidal extension (ETE) and concomitant thyroiditis were collected from 374 untreated PTMC patients from Guangdong, China. Univariate and multivariate analyses were performed to identify clinicopathologic predictors of LNM and prognostic indicators in PTMC patients with LNM. Results: During the follow-up period of 120 months, recurrence was significantly higher in patients with LNM than in patients without LNM (P<0.05). Age <45 years, larger tumor (>5 mm) and multifocality were predictors of LNM; age <45 years, larger tumor size and absence of concomitant thyroiditis were associated with central LNM (CLNM); male sex, ETE and multifocality were correlated with lateral LNM (LLNM) (P<0.05). There was no difference in recurrence between patients with CLNM and LLNM (P>0.05). LNM in PTMC primarily influenced disease-free survival. Age >45 years and male sex were risk factors of recurrence in PTMC patients with LNM. Male patients with CLNM and older patients with LLNM exhibited worse prognosis (P<0.05). Conclusions: PTMC easily metastasizes to cervical lymph nodes, which significantly influences prognosis. Prophylactic LND is recommended in PTMC patients from Guangdong, China, who have a high risk of CLNM and/or LLNM. More aggressive postoperative treatment and more frequent follow-up could be considered for older and/or male PTMC patients with LNM.