The Role of Primary Tumor Surgery in Oligometastatic Breast Cancer: A Meta-Analysis of Randomized and Observational Studies.

We conducted an up-to-date meta-analysis to evaluate the role of locoregional surgical intervention for the primary tumor in patients with oligometastatic breast cancer (OMBC). A comprehensive literature search was conducted to identify randomized controlled trials (RCTs) and retrospective cohort studies (RCS) comparing primary tumor resection plus systemic therapy versus systemic therapy alone in metastatic breast cancer. Subsequently, relevant subgroups of patients with OMBC were selected from these studies. The hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) were assessed and pooled. A total of 16 studies comprising 3358 patients were included. We ultimately included 3 RCTs, 1 non-randomizedcontrolled trial (NRCT), and 12 RCSs. The results demonstrated that the combination of surgical intervention for the primary tumor with systemic therapy significantly improved both OS and PFS compared to systemic therapy alone. The pooled results for OS showed an HR of 0.61 (95% CI, 0.48-0.79) for controlled trials and an HR of 0.68 (95% CI, 0.61-0.74) for RCSs. Furthermore, a significant improvement in PFS was observed (HR = 0.66, 95% CI, 0.52-0.83). This study collectively demonstrates a substantial survival benefit for the treatment strategy combining surgical intervention with systemic therapy in patients with OMBC. These findings suggest that this multimodal approach may offer a viable therapeutic option for OMBC.