Implant-based reconstruction and adjuvant radiotherapy in breast cancer patients-current status and DEGRO recommendations.

Purpose: The aim of this review is to give an overview of the results of prospective and retrospective studies using allogenic reconstruction and postmastectomy radiotherapy (PMRT) in breast cancer and to make recommendations regarding this interdisciplinary approach.

Materials and methods: A PubMed search was conducted to extract relevant articles from 2000 to 2024. The search was performed using the following terms: (breast cancer) AND (reconstruction OR implant OR expander) AND (radiotherapy OR radiation). Data from the literature on allogenic breast reconstruction and radiation are presented and discussed in relation to toxicity and cosmesis.

Conclusion and recommendations: Breast reconstruction is also feasible if PMRT is necessary. Patients need to be informed about the relevant risk of capsular fibrosis and implant failure. A planned reconstruction is no reason to forgo PMRT nor is an indication for PMRT a reason to forego implant-based breast reconstruction if desired by the patient. It is important to provide detailed information here to enable shared decision-making. There is still no clear consensus regarding implant-based reconstruction (IBR) and PMRT. However, in clinical practice, both a one-stage (immediate "implant-direct" IBR) procedure with PMRT up to the final implant and a two-stage (immediate-delayed IBR) procedure with PMRT up to the tissue expander (TE) and later exchange of the TE are used; both approaches have their specific advantages and disadvantages. Depending on patient-specific factors and the surgeon's experience and estimates, both IBR procedures are also possible in combination with PMRT. When using a TE/implant approach, completing skin stretching by adequately filling the expander before PMRT may be favorable. This approach is particularly practical when adjuvant chemotherapy is planned but may lead to postponement of radiotherapy when primary systemic therapy is given. According to the latest data, moderate hypofractionation also appears to be safe in the context of the IBR approach. It is important to have a closely coordinated interdisciplinary approach and to fully inform patients about the increased rate of potential side effects.