Radiotherapy After Skin-Sparing Mastectomy and Implant-Based Breast Reconstruction.

INTRODUCTION: We evaluated the cosmetic results of radiotherapy (RT) after implant-based reconstruction (IBR). PATIENTS AND METHODS: We retrospectively evaluated 170 patients with 171 breast cancers treated between December 2004 and January 2016 in 2 university hospitals. RT fields were reconstructed breast (RB) only in 24 (14%), and RB and regional lymphatics in 147 (86%) breasts, respectively. All but 1 patient received a total 50 Gy with conventional fractionation. All patients received systemic chemotherapy. One hundred thirty-eight (81%) patients received hormonal therapy; 118 tamoxifen and 20 aromatase inhibitor. RESULTS: Median follow-up time was 46.8 months (range, 1-163 months). The 5-year disease-free and overall survival rate was 83% and 93%, respectively. Cosmetic results were considered excellent in 111 (65%), fair in 46 (27%), and bad in 14 (8%) RB by patients. Thirty-four (20%) RB had restorative surgery; because of surgeons' preference because of implant natural life time span in 5, and contracture, fibrosis, deformation, or dislocation of the implant, or cellulitis in the remaining. Statistically significant adverse factors in univariate analysis for impaired cosmetic outcome were bolus use on the RB, lymphatic irradiation, and volume that received at least 110% of the prescribed dose being > 1%. The use of bolus material was the only prognostic factor for deterioration of the cosmetic result in multivariate analysis. CONCLUSION: RT after IBR yields acceptable cosmetic results. Although only 111 (65%) of RBs were considered to have excellent cosmetic results, only a small percentage of patients needed reoperation because of bad cosmetic outcome.