Preoperative thyroglobulin antibody positivity is associated with delayed absorption after microwave ablation for papillary thyroid carcinoma

BACKGROUND: Microwave ablation (MWA) has emerged as a minimally invasive alternative to surgery for selected patients with low-risk papillary thyroid carcinoma (PTC). While thyroid autoimmunity is frequently observed in PTC, the impact of preoperative thyroid autoantibodies (TAb) on post-ablation absorption kinetics remains unclear. METHODS: This retrospective study included 150 patients with PTC who underwent MWA between December 2019 and December 2024 with a median follow-up of 18 months (range: 6-54 months). Patients were categorized according to preoperative thyroid autoantibody status. Volume reduction rate, complete absorption rate, tumor recurrence rate, incidence of new nodules, and thyroid function were evaluated during follow-up. Kaplan-Meier analysis and Cox proportional hazards regression were used to assess factors associated with time to complete absorption. RESULTS: = 0.015). No malignant recurrence occurred. TPOAb-positive patients showed a higher incidence of newly detected benign nodules. Thyroid function remained stable throughout follow-up. CONCLUSIONS: Preoperative TgAb positivity is associated with delayed absorption of the ablation zone after MWA for PTC without compromising treatment completeness.