biostudies-literatureChen XGuangzhou Science, Technology and Innovation Commission (Bureau of Science and Information Technology of Guangzhou Municipality)Sun Yat-sen University (SYSU)Natural Science Foundation of Guangdong Province (Guangdong Natural Science Foundation)National Natural Science Foundation of China (National Science Foundation of China)9144https://www.ebi.ac.uk/biostudies/studies/S-EPMC11500097biostudies-literatureUnknown15(1)Oral corticosteroids represents the most prevalent treatment for idiopathic granulomatous mastitis. Ductal lavage with triamcinolone acetonide and antibiotics followed by observation (DL-OBS) has emerged as a novel strategy, but a comparison of them remains lacking. Here in this multicenter, open-label, non-inferiority, randomized trial (ClinicalTrials.gov identifier: NCT03724903), we assigned 140 patients to oral corticosteroids (N = 71) and DL-OBS (N = 69), stratified by baseline M-score. The primary outcome is complete Clinical Response rate at 1 year. The non-inferiority margin is -15%. The primary outcome is 85.5% in DL-OBS and 87.3% in oral corticosteroids (difference: -1.8%; 95%CI, 13.2 to 9.5; P_{non-inferiority} = .01) in intention-to-treat population, and 92.6% vs 98.2% (Nature communicationsDuctal lavage followed by observation versus oral corticosteroids in idiopathic granulomatous mastitis: A randomized trial.PMC11500097#2019A1515011467, #2019A1515110075 and #2021A1515012361#202102010221#82271650#SYS-Q-202002, #20180233Hu TZhang JHuang HYu FSu LLiu QLiu SGui XDing LJiang YChen XWu WWang YZhao JRao NTan LChen QChen KTan CZeng YXiao QYe LLi YYang YLi SYong JZhu LCai XXu YfalseDuctal lavage followed by observation versus oral corticosteroids in idiopathic granulomatous mastitis: A randomized trial.Oral corticosteroids represents the most prevalent treatment for idiopathic granulomatous mastitis. Ductal lavage with triamcinolone acetonide and antibiotics followed by observation (DL-OBS) has emerged as a novel strategy, but a comparison of them remains lacking. Here in this multicenter, open-label, non-inferiority, randomized trial (ClinicalTrials.gov identifier: NCT03724903), we assigned 140 patients to oral corticosteroids (N = 71) and DL-OBS (N = 69), stratified by baseline M-score. The primary outcome is complete Clinical Response rate at 1 year. The non-inferiority margin is -15%. The primary outcome is 85.5% in DL-OBS and 87.3% in oral corticosteroids (difference: -1.8%; 95%CI, 13.2 to 9.5; P_{non-inferiority} = .01) in intention-to-treat population, and 92.6% vs 98.2% (2024-01-01T00:00:00Z2024 Oct2026-07-15T08:05:29.682Z2025-04-04T02:57:23.917ZS-EPMC115000973944344610.1038/s41467-024-53143-2