LAUSR

1082Background: Current guidelines lack definitive evidences about the relative benefits of locoregional surgery for the primary tumor in de novo stage IV breast cancer. The aim of this study was to comprehensively investigate the role of locoregional surgery for primary tumor in de novo stage IV breast cancer. Methods: We conducted a Chinese multicenter real-world study of patient-level data to investigate the effect of locoregional surgery versus no surgery of the primary tumor in de novo stage IV breast cancer. We used propensity score matching to compare similar patients who underwent locoregional surgery and no surgery. Overall survival (OS) was estimated using the Kaplan-Meier method and the log-rank test. A meta-analysis also was performed of prospective and retrospective studies, respectively. Results: Among 353 patients, 189 (53.6%) received locoregional surgery and 164 (46.4%) underwent no surgery. We matched 202 patients treated with locoregional surgery with similar patients who received no su...