Does post-mastectomy radiation therapy worsen outcomes in immediate autologous breast flap reconstruction? A systematic review and meta-analysis.

BACKGROUND There is great uncertainty regarding the practice of immediate autologous breast reconstruction (IBR) when post-mastectomy radiotherapy (PMRT) is indicated. Plastic surgery units differ in their treatment protocols, with some recommending delayed breast reconstruction (DBR) following PMRT. IBR offers significant cosmetic and psychosocial benefits; however, the morbidity of flap exposure to radiation remains unclear. OBJECTIVE The aim of this review was to comprehensively analyze the existing literature comparing autologous flaps exposed to PMRT and flaps with no radiation exposure. METHODS A comprehensive search in MEDLINE, EMBASE and CENTRAL databases was conducted in November 2020. Primary studies comparing IBR with and without adjuvant PMRT were assessed for the following primary outcomes: clinical complications, observer-reported outcomes and patient-reported satisfaction rates. Meta-analysis was performed to obtain pooled risk ratios of individual complications. RESULTS Twenty-one articles involving 3817 patients were included. Meta-analysis of pooled data gave risk ratios for fat necrosis (RR = 1.91, p < 0.00001), secondary surgery (RR = 1.62, p = 0.03) and volume loss (RR = 8.16, p < 0.00001) favoring unirradiated flaps, but no significant difference was observed in all other reported complications. The no-PMRT group scored significantly higher in observer-reported measures. However, self-reported aesthetic and general satisfaction rates were similar between groups. CONCLUSION IBR should be offered after mastectomy to patients requiring PMRT. The higher risks of fat necrosis and contracture appear to be less clinically relevant as corroborated by positive scores from patients developing these complications. Preoperative and intraoperative measures should be taken to further optimize reconstruction and mitigate post-radiation sequel. Careful management of patients' expectations is also imperative. LEVEL OF EVIDENCE Level III.