Factores de riesgo de metástasis ganglionares en el microcarcinoma papilar de tiroides

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 <.001) and radioactive iodine (24.7% vs. 100%; P <.001). During a mean follow-up of 119.8 +/- 65 months, one recurrence was detected in group 2 (0% vs. 6.7%; P =.093). No patients died due to the disease. 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. (C) 2019 AEC. Published by Elsevier Espana, S.L.U. All rights reserved.