Abstract P2-15-04: Surgical outcomes of ambulatory mastectomy with immediate alloplastic reconstruction for breast cancer or risk reduction

Abstract Purpose: Since 2015, mastectomy with immediate implant-based reconstruction at our institution is an ambulatory “day surgery” procedure. Ambulatory criteria for surgery including ASA level, BMI and major comorbidities were used to screen patients. We aim to evaluate surgical outcomes for women who undergo ambulatory mastectomy with immediate alloplastic reconstruction for breast cancer or risk reduction. Our primary objective was to determine the impact of mastectomy type (nipple- or skin-sparing mastectomy) and device location (subpectoral versus prepectoral plane) on complication rates. Methods: We performed a retrospective cohort study of women receiving immediate alloplastic reconstruction following mastectomy for either breast cancer or risk reduction at Women’s College Hospital in Toronto, Ontario, Canada between 2015 and 2021. We collected demographic data on age, ethnicity, smoking status, and menopausal status. Clinical data collected included breast size, ptosis, surgical indications, laterality, location and type of implant, type of mesh used, and overall complication rate. We used a multivariable logistic regression model to determine the impact of mastectomy type and implant location on complication rates, with age, smoking status, breast size, ptosis, surgical indication, and use of mesh as covariates. Statistical analysis was performed using SAS® OnDemand for Academics and P values < 0.05 were considered statistically significant. Results: 284 women underwent mastectomy with immediate alloplastic reconstruction for risk reduction (130, 45.8%) and breast cancer (154, 54.2%). 134 (47%) underwent skin-sparing mastectomy (SSM) and 149 (53%) underwent nipple-sparing mastectomy (NSM). Demographic and clinical data are presented in Table 1. There was an overall complication rate of 19.4%; women having NSM had a higher crude complication rate compared with SSM (25.5% vs 12.6%, P = 0.006). In our multivariable logistic regression model, there was no interaction between mastectomy type and device location on complication rate (P = 0.5). There was also no difference in complication rates associated with SSM compared with NSM (OR 2.9, 95% CI 0.95 – 9.0, P = .06) or implant location (P = 0.1). Younger age (OR 0.93/year increase in age, 95% CI 0.89-0.98, P = 0.005) and having surgery for breast cancer (OR 3.4, 95% CI 1.1 – 10.2, P = 0.03) were associated with an increased likelihood of complications. Conclusion: In women undergoing ambulatory mastectomy with immediate alloplastic reconstruction for breast cancer or risk reduction, there was no impact of mastectomy type (SSM vs NSM) or implant location (subpectoral vs prepectoral) on complication rates. Non-modifiable factors such as age and having surgery for breast cancer predicted having a complication. Our data suggest that with appropriate patient selection, there is no difference in surgical outcomes between mastectomy types and implant location in the ambulatory surgery setting. Table 1.1 Total Cohort Demographic and Clinical Data Table 1.2 Total Cohort Demographic and Clinical Data Citation Format: Simran Sandhu, Tulin D. Cil, Jaime M. Escallon, Mitchell Brown, John Semple, David Lim. Surgical outcomes of ambulatory mastectomy with immediate alloplastic reconstruction for breast cancer or risk reduction. [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-15-04.