Microwave Ablation Versus Thyroid Lobectomy for Solitary cT1aN0M0 Papillary Thyroid Carcinoma: A Prospective Multicenter Cohort Study

Objective To determine whether thermal ablation could serve as an alternative to surgery in solitary clinically node-uninvolved papillary thyroid carcinoma ≤1 cm (cT1aN0M0 PTC). Patients and Methods This comparative study was performed across 12 tertiary hospitals and enrolled patients from December 1, 2019 to December 31, 2020. A total of 895 patients with cT1aN0M0 PTC were enrolled and assigned to either the microwave ablation (MWA) group or the surgery group after multidisciplinary consultation. Primary outcomes, including the disease progression, tumor volume changes, complications, and postoperative quality of life, were compared. Subgroup analyses and multimode analysis were performed. Results Total of 444 patients in the MWA group and 439 in the surgery group were included in the final analysis. The disease progression rate was 1.14% in the surgery group and 2.48% in the MWA group with a mean follow-up of 42 months. The noninferiority of MWA to surgery was not statistically significant ( P <.05 for noninferiority with a predefined noninferiority margin of 2.0%). The MWA yielded comparable lymph node metastasis and disease progression outcomes compared with surgery ( P >.05). The overall complication rates were similar between groups ( P =.08). Shorter hospitalization, lower cost, lower anxiety scores, and fewer scar-related concerns were observed in the MWA group ( P <.01). Conclusion The MWA achieved noninferior clinical efficacy compared with thyroid lobectomy for cT1aN0M0 PTC, with faster recovery, lower cost, and fewer anxiety-related concerns. The MWA may serve as a de-escalation treatment option for patients seeking nonsurgical treatment. Trial Registration Clinicaltrials.gov Identifier: NCT04197960