LAUSR

Abstract Introduction Papillary thyroid microcarcinoma (PTMC) usually has an indolent course, but some have worse prognostic factors, such as the presence of central (6.9%–51.5%) and lateral (3%–49.6%) lymph node metastases. The aim of this study is to analyze the factors associated with PTMC with metastatic lymph nodes and its long-term prognosis. Methods Retrospective study whose study population consists of patients with PTMC (size ≤1 cm). Patients with previous thyroid surgery, other synchronous malignancies and ectopic location of the PTMC were excluded. Two groups were compared: PTMC without metastatic lymph nodes (group 1) and PTMC with metastatic lymph nodes (group 2). A multivariate analysis using a logistic regression model and a Kaplan–Meier survival analysis with log-rank test were performed. Results Out of the 161 selected patients, 9.3% (n=15) had metastatic lymph nodes. Multifocality (OR 5.284, 95%CI 1.056–26.443; P=.043) and extrathyroidal extension (OR 7.687, 95%CI 1.405–42.050; P=.019) were associated with the presence of metastatic lymph nodes. In PTMC with metastatic lymph nodes, more aggressive treatments were performed: lymphadenectomy (4.8% vs. 100%; P Conclusions Multifocality and extrathyroidal extension of PTMC were associated with the presence of metastatic lymph nodes. Metastatic PTMC, with more aggressive treatments, presents an excellent long-term prognosis.