Is oncoplastic surgery a contraindication for accelerated partial breast radiation using the interstitial multicatheter brachytherapy method?

Purpose: To evaluate accelerated partial breast irradiation (APBI) in patients after oncoplastic surgery for early breast cancer. Methods and Materials: A retrospective analysis of 136 breasts of 134 patients, who received breast-conserving oncoplastic surgery for low-risk breast cancer between 2002 and 2010 in the Universities of Vienna and Luebeck followed by adjuvant APBI applying total doses of pulse dose rate of 50.4Gy or high-dose rate (HDR) of 32Gy over 4days. Target volume definition was performed by the use of surgical-free margin data, related to intraoperatively fixed clip positions, pre- and postoperative imaging, and palpation. Results: At the time of data acquisition, 131 of 134 patients were alive. The median follow-up time was 39months (range, 4-106 months). After high-dose rate treatment, 3 of 89 patients showed systemic progress after a mean follow-up of 47months (range, 19-75 months) and 2 patients had a different quadrant in-breast tumor after 27 and 35months. One patient died 7months after treatment of unknown causes. After pulse dose rate treatment, 1 of 45 patients had a local recurrence after 42months and 1 patient died because of another cause after 13months. We observed mild fibrosis in 27 breasts, telangiectasia in 6, hyperpigmentation in 14 cases, and keloid formation in1. Conclusions: These preliminary results suggest the feasibility of multicatheter APBI after oncoplastic breast-conserving surgery in selected low-risk breast cancer patients; however, special attention to target volume definition is needed. Further prospective investigations with long follow-up are needed to define the real value of the procedure.