Efficacy and safety of oncoplastic breast-conserving surgery versus conventional breast-conserving surgery: An updated meta-analysis

Introduction: Breast cancer is the most common cancer among women. The surgical treatment of breast cancer has transitioned progressively from radical mastectomy to breast-conserving surgery. In this meta-analysis, we are aiming to compare oncoplastic breast-conserving surgery (OS) with conventional breast-conserving surgery (BCS) in terms of efficacy and safety. Methods: We searched Medline, Web of Science, Embase, Cochrane databases, Clinicaltrial.gov, and CNKI until April 30, 2024. Data from cohort studies and randomized controlled trials (RCTs) were included. Outcomes included primary outcomes (re-excision, local recurrence, positive surgical margin, mastectomy), secondary outcomes and safety outcomes. The Cochrane Risk of Bias Assessment Tool and Newcastle-Ottawa Scale were used to evaluate the quality of outcomes. Results: Our study included 52 studies containing 46,835 patients. Primary outcomes comprise re-excision, local recurrence, positive surgical margin, and mastectomy, there were significant differences favoring OS over BCS (RR 0.68 [0.56, 0.82], RR 0.62 [0.47, 0.82], RR 0.76 [0.59, 0.98], RR 0.66 [0.44, 0.98] respectively), indicating superior efficacy of OS. Additionally, OS demonstrated significant aesthetic benefits (RR 1.17 [1.03, 1.33] and RR 1.34 [1.18, 1.52]). While total complications were significantly fewer in the OS group (RR 0.70 [0.53, 0.94]), the differences in specific complications were not significant. Furthermore, subgroup analyses were conducted based on nationality, sample size, quality, and type. Conclusion: OS demonstrates either superior or at least comparable outcomes across various aspects when compared to BCS.