Propensity-matched comparison of microwave ablation and surgical resection for preoperative T1N0M0 papillary thyroid carcinoma: 5-year follow-up.

[BACKGROUND] Microwave ablation (MWA) has demonstrated short-term efficacy comparable to surgical resection (SR) for papillary thyroid carcinoma (PTC), but long-term data are limited.

[OBJECTIVE] To compare the long-term efficacy and safety of MWA versus SR in preoperative T1N0M0 PTC.

[MATERIALS AND METHODS] This single-center retrospective study included 792 patients with preoperative T1N0M0 PTC treated with MWA or SR from January 2016 to June 2019. Propensity score matching (PSM) balanced baseline characteristics between the MWA and SR groups, while inverse probability of treatment weighting (IPTW) was used for subgroup analyses between the MWA and total thyroidectomy (TT) or lobectomy (LT) groups. Primary outcomes were disease progression-free survival (DFS), thyroid recurrence-free survival (TRFS), lymph node recurrence-free survival (LRFS), and complication rates. Secondary outcomes were treatment variables, ablation zone volume reduction and disappearance rates.

[RESULTS] Following PSM, 464 patients (median age 41 years; 343 females) were followed for a median of 69 months. No significant difference in DFS was observed between the MWA and SR groups. LRFS did not significantly differ between the two groups. TRFS was lower in the MWA group than in the SR group and the TT subgroup, but not different from the LT subgroup. The MWA group had fewer complications, with permanent hoarseness only in the SR group. MWA also resulted in shorter incisions, reduced operative and hospitalization times.

[CONCLUSION] MWA offers comparable long-term efficacy to surgery for preoperative T1N0M0 PTC, with fewer complications.

[KEY POINTS] Question What are the long-term outcomes of MWA compared to surgery for preoperative T1N0M0 papillary thyroid carcinoma? Findings Over a median follow-up of 69 months, the MWA group showed comparable disease-free survival but a lower complication rate than the SR group. Clinical relevance This study provides long-term comparative data on MWA and surgery for preoperative T1N0M0 papillary thyroid carcinoma, offering valuable insights for clinical decision-making.