Factors for lymph node metastasis and survival rate in papillary thyroid microcarcinoma: from a large cohort of 3 607 cases series

Abstract

Objective: To investigate high-risk factors for lymph node metastasis (LNM) and 10-year survival rate in patients with papillary thyroid microcarcinoma (PTMC). Methods: We retrospectively analyzed the clinical data of 3 607 patients with PTMC received surgery in our hospital from January 2005 to December 2015. Univariate and multivariate analyses were performed to identify the factors associated with metastasis and 10-year survival rate of the patients was calculated. Results: The patients accepted an average follow-up of 68 months, with follow-up from 18 to 138 months. Total LNM rate in the 3 607 patients with PTMC was 17.13%. Central lymph node metastasis rate was 16.86%, which was related to gender (males 21.89% vs females 15.26%, P<0.01), age (<45 years old 24.44% vs ≥45 years old 11.96%, P<0.01), tumor diameter (P<0.01) and multifocality (P<0.01). Lateral lymph node metastasis rate was 1.05%, which was related to age (<45 vs ≥45, P<0.01) and tumor diameter (P<0.01). The 10-year-survival rate was 93.0% and 10-year recurrence-free survival rate was 87.5%. Conclusion: PTMC may metastasize to cervical lymph node, especially in males, with age younger than 45, multifocal tumors and maximal tumor diameter larger than 0.7 cm. There was no significant correlation between these clinical features associated with LNM and the 10-year survival rate.