[Radiotherapy and delayed breast reconstruction with implant: examination of compatibility]

Delayed breast reconstruction with implant is frequently used after mastectomy. However, given that many breast cancer patients receive adjuvant radiotherapy, the adaptation of this method raises questions concerning possible cumulative complications. In the present study the compatibility of post-mastectomy radiotherapy and delayed breast reconstruction with implant was examined.

We evaluated a consecutive series of 66 invasive breast cancer patients who have received delayed breast reconstruction with implant after modified radical mastectomy between January 1997 and June 1999. The average time was 51 months from primary surgery to reconstruction. The median dose of loco-regional irradiation was 50 Gy. Grade III atrophic dermatitis was observed in none of the irradiated women. We identified two patient groups: 29 patients did not and 37 patients did receive post-mastectomy radiotherapy. The types and time of reconstruction related chronic complications (capsular contracture, defect of implant shell and skin necrosis) were recorded. Incidence of complications was estimated by the Kaplan-Meier method. Cancer related events were also studied.

When expander was used, minor discomfort of the patients was common during the filling course. At four (11%) irradiated patients the expansion with expander was incomplete, due to severe pain. At a median follow up time of 53 months the incidence of capsular contracture was 24.1% without and 29.7% with radiotherapy (p=0.4121). The five-year estimated rate of late complications was 40% and 50%, respectively (relative risk: 1.29, 95% confidence interval: 0.58-2.89, p=0.5173). The position of implant had an impact on the incidence of capsular contracture: 46.2% with subcutaneous and 22.6% with submuscular position (p=0.0881). Four patients (6%) developed local relapse (three in the skin and one subcutaneous). All were treated with tumor excision without implant removal.

Delayed breast reconstruction with implant after post-mastectomy radiotherapy can be offered to patients who are interested in breast reconstruction and had no severe late radiation skin toxicity. Post-mastectomy radiotherapy does not significantly increase the risk of complications. The use of skin expander is less tolerated by irradiated patients. Submuscular position of implants moderates the risk of capsular contracture.