Coexistent Hashimoto’s thyroiditis modulates lymph node metastasis burden in papillary thyroid carcinoma: a single-center study in South China
TL;DR
Concomitant HT is associated with a reduced metastatic burden rather than an increased prevalence of CLNM in patients with papillary thyroid carcinoma (PTC), and the necessity of prophylactic central lymph node dissection warrants individualized assessment combining clinical data and intraoperative observations to avoid overtreatment.
Abstract
Objective To investigate the impact of Hashimoto’s thyroiditis (HT) on central lymph node metastasis (CLNM) patterns and identify independent risk factors for CLNM in patients with papillary thyroid carcinoma (PTC). Methods This retrospective study enrolled 668 cN0 PTC patients who underwent initial surgery at Huizhou Central People’s Hospital between August 2024 and July 2025. Patients were stratified into an HT-PTC group (n = 117) and a PTC-only group (n = 551) based on postoperative histopathological findings. Clinicopathological features and CLNM characteristics were systematically compared. Multivariable logistic regression was utilized to identify independent risk factors for CLNM in patients with HT-PTC, and the predictive efficacy of the resulting model was validated using ROC curves. Results The HT-PTC group exhibited significantly higher rates of multifocality and central lymph node dissection, alongside lower BMI and serum thyroglobulin (Tg) levels, compared with the PTC-only group (all P < 0.05). While the incidence of CLNM did not differ significantly between groups (35.0% vs. 33.9%, P = 0.819), the metastatic lymph node ratio (LNR) was significantly lower in the HT-PTC group (P < 0.001). Multivariate analysis identified tumor diameter > 1 cm as an independent risk factor for CLNM among HT-PTC patients (OR = 3.678; 95% CI: 1.587–8.520, P = 0.002). The predictive model demonstrated moderate efficacy (AUC = 0.649). Notably, the incidence of CLNM in HT-PTC patients with microcarcinoma (≤ 1 cm) was only 25.9%. Conclusion Concomitant HT is associated with a reduced metastatic burden rather than an increased prevalence of CLNM in patients with PTC. Tumor diameter > 1 cm serves as an independent predictor of CLNM. For HT-PTC patients with tumors ≤ 1 cm and no other high-risk factors, the necessity of prophylactic central lymph node dissection warrants individualized assessment combining clinical data and intraoperative observations to avoid overtreatment.