Postmastectomy Radiotherapy With Immediate Implant Reconstruction: Treatment Fractionation, Implant Plane, and...

Immediate implant-based breast reconstruction (IBR) after mastectomy raises concerns when postmastectomy radiotherapy (PMRT) is required. While conventional PMRT has traditionally used 50 Gy in 25 fractions, hypofractionated schedules are increasingly adopted. This narrative review aims at summarizing current evidence and guideline recommendations regarding hypofractionated PMRT in patients undergoing implant-based reconstruction and evaluates whether implant placement (prepectoral vs. subpectoral) influences outcomes. To this purpose, a literature search was performed across major biomedical databases, including PubMed, Embase, Cochrane Library, and Google Scholar, to identify international guidelines, randomized controlled trials, systematic reviews, and cohort studies evaluating PMRT fractionation in the setting of IBR. Eligible publications addressed oncologic outcomes, reconstruction-related complications, and the influence of implant placement (prepectoral vs. subpectoral). Overall, current consensus guidelines support moderate hypofractionation (40-42.5 Gy in 15-16 fractions) for chest wall irradiation, including patients with implant reconstruction. Randomized trials demonstrate equivalent locoregional control and toxicity compared with conventional fractionation. Emerging data from reconstructed cohorts, including randomized and phase III studies, indicate no increase in reconstruction-related complications with hypofractionated PMRT. Evidence regarding implant plane remains mixed: some studies report higher capsular contracture rates following subpectoral reconstruction, whereas larger contemporary series and systematic reviews demonstrate comparable complication and failure rates between prepectoral and subpectoral placement. In conclusion, available evidence supports the safety and effectiveness of moderately hypofractionated PMRT in patients undergoing immediate IBR. Implant plane selection should be individualized, taking into account patient anatomy, cosmetic considerations, and overall risk profile. Ongoing prospective studies will further clarify long-term outcomes.