Predictive Factors of Lymph Node Metastasis in Papillary Thyroid Microcarcinoma (PTMC)

Background and Objectives: The incidence of papillary thyroid microcarcinoma (PTMC) has increased. Some patients present with lymph node metastases (LNM), while risk factors remain unclear. This study aims to examine clinicopathological markers predictive of LNM in PTMC. Materials and Methods: We retrospectively analyzed 170 patients with a histological diagnosis of PTMC. The patients were grouped based on the presence of LNM. Results: Our cohort consisted of 133 females and 37 males, aged 47.14 ± 12.81 years. Twenty-seven (15.9%) individuals had LNM. Median tumor size was 5 mm (4.25, 0.15-10), and multifocality was present in 37.1% of patients. Thyroid capsular invasion (TCI) was observed in 22.9% of patients. Extrathyroidal extension (ETE) and aggressive variants were present in 12.9% and 8.8% of patients, respectively. Forty-four patients had a history of autoimmune thyroid disease. From univariate analysis, age < 55 years (OR: 6.317; p = 0.015), TCI (OR: 2.824; p = 0.020), and ETE (OR: 2.987; p = 0.034) were independent predictors of LNM. Multivariate analysis showed that younger patients are at a significantly increased risk of LNM in PTMC (OR: 6.30910; p = 0.016). Conclusions: The findings of this study highlight the need for greater attention to PTMC in younger patients with ultrasonographic features of TCI and ETE, as they may require a more thorough evaluation of LNM, strict follow-up, and may benefit from a surgical decision of lymphadenectomy.