Oncoplastic breast conserving surgery (OBCS): A meta-analysis of real-world data

Abstract Background: The role of oncoplastic breast conserving surgery (OBCS) is that of a middle ground between standard breast conserving surgery (SBCS) and mastectomy - it allows adequate resection margins of tumours unsuitable for traditional breast conserving surgery whilst allowing for a better cosmetic outcome and a reduced morbidity rate when compared to a traditional mastectomy. However, due to this being a relatively new type of procedure, there is limited evidence on its oncological safety, which is the ultimate goal of any breast cancer surgery. Methods: This study aims to compare oncological safety of OBCS with SBCS and mastectomy by examining the relative risk of cancer recurrence and re-operation rates through meta-analysis. Literature search of Pubmed and Web of Science databases was conducted looking for studies up until February 2019. Meta-Analysis was performed using R Statistical Software (www.r-project.org). Results: Initial finding of 645 studies was narrowed down to a pool of 19 studies including 18,163 patients. For the primary outcome measure of recurrence there was found to be no significant difference between the OBCS and SBCS or mastectomy (RR 0.861; 95% CI 0.640-1.160; p<0.296). The secondary outcome measure of re-operation was initially found to be significant in favour of OBCS (RR 0.64; 95% CI 0.46-0.89; p<0.01), however after adjustment for publication bias this was attenuated to an insignificant difference between the two study groups (RR 0.86; 95% CI 0.56-1.31; p>0.05). Conclusions: For both recurrence of cancer and re-operation rate, there was not found to be a significant difference between OBCS and more traditional techniques. This would suggest that OBCS is of comparable oncological safety to more established operations and a useful option in suitable patients. Citation Format: Sebastian Kosasih, Salim Tayeh, Kefah Mokbel, Abdul Kasem. Oncoplastic breast conserving surgery (OBCS): A meta-analysis of real-world data [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-13-09.