Prepectoral vs. Submuscular Immediate Breast Reconstruction in Patients Undergoing Mastectomy after Neoadjuvant Chemotherapy: Our Early Experience

Background: Conservative mastectomy with immediate prosthetic breast reconstruction (IPBR) is an oncologically accepted technique that offers improved esthetic results and patient quality of life. Traditionally, implants have been placed in a submuscular (SM) plane beneath the pectoralis major muscle (PMM). Recently, prepectoral (PP) placement of the prosthesis has been increasingly used in order to avoid morbidities related to manipulation of the PMM. The aim of this study was to compare outcomes of SM vs. PP IPBR after conservative mastectomy in patients with histologically proven breast cancer treated with neoadjuvant chemotherapy (NAC). Methods: In this retrospective observational study, we analyzed two cohorts of patients that underwent mastectomy with IPBR after NAC in our institution from January 2018 to December 2021. Conservative mastectomy was performed in 146 of the 400 patients that underwent NAC during the study period. Patients were divided into two groups based on the positioning of implants: 56 SM versus 90 PP. Results: The two cohorts were similar for age (mean age 42 and 44 years in the SM and PP group respectively) and follow-up (33 and 20 months, respectively). Mean operative time was 56 min shorter in the PP group (300 and 244 min in the SM and PP group). No significant differences were observed in overall major complication rates. Implant loss was observed in 1.78% of patients (1/56) in the SM group and 1.11% of patients (1/90) in PP group. No differences were observed between the two groups in local or regional recurrence. Conclusions: Our preliminary experience, which represents one of the largest series of patients undergoing PP-IPBR after NAC at a single institution documented in the literature, seems to confirm that PP-IPBR after NAC is a safe, reliable and effective alternative to traditional SM-IPBR with excellent esthetic and oncological outcomes; it is easy to perform, reduces operative time and minimizes complications related to manipulation of PPM. However, this promising results need to be confirmed in prospective trials with longer follow-up.