Efficacy and safety of microwave ablation for the treatment of multifocal versus unifocal T1N0M0 papillary thyroid carcinoma: a propensity-matched multicentre retrospective study.

• Microwave ablation for multifocal and unifocal T1N0M0 papillary thyroid carcinoma had similar tumour progression rates after propensity score matching (6.7% vs. 4.3%, p = 0.33). • The tumour disappearance rate in the multifocal group was lower than that in the unifocal group (40.9% vs. 62.8%, p < 0.001), and tumour disappearance was slower in the multifocal group (p < 0.001). • Tumour size, number, and location were not risk factors for tumour progression in the multifocal papillary thyroid cancer group.