Acellular dermal matrix in implant-based immediate breast reconstructions: a comparison of prepectoral and subpectoral approach

Background: Implant-based immediate breast reconstruction (IBR) is the most common technique for post-mastectomy reconstructions in the United Kingdom (UK). Subpectoral implant placement is the conventional method of reconstruction. Placement of implant in the subcutaneous pocket covered by an acellular dermal matrix (ADM) is a relatively recent approach. We report a comparative analysis of prepectoral versus subpectoral approach for implant-based IBR from a single institution in the UK. Methods: Retrospective analysis from a prospectively maintained data was conducted from January 2015 to May 2017 including all patients who underwent a mastectomy with immediate implant-based IBR in a single breast unit. The demographic details, operative details, immediate and delayed complications were recorded. Specific complications recorded were infection, seroma, unplanned readmission and loss of implant. Factors affecting complication rates and implant loss were analyzed. Results: One hundred and fifty-four reconstructions were included in the analysis with a median follow-up of 11.8 months. Mean age of the cohort was 50 years with a mean BMI of 26.09 kg/m(2). Major implantrelated complication rate was 12.3% with an implant loss rate of 7.8%. Age more than 50 years (P=0.037) and bilateral reconstructions (P=0.0001) had significant impact on complication rate, on multivariate analysis. Patients with bilateral implants had a significantly higher implant loss rate (P=0.0001). Implant loss rates in the prepectoral group (4.2%) and subpectoral group (10.8%) were not statistically significant (P=0.29). Conclusions: Prepectoral and subpectoral techniques of IBR have comparable outcomes. Studies reporting on long-term outcomes are planned.