Accelerated partial breast irradiation with multi-catheter brachytherapy: Local control, side effects and cosmetic outcome for 274 patients. Results of the German-Austrian multi-centre trial.

Abstract

To evaluate the safety and effectiveness of accelerated partial breast irradiation (APBI) with multi-catheter brachytherapy. Between 11/2000 and 04/2005, 274 patients participated. Patients were eligible for APBI if they had histologically confirmed breast cancer, a tumour diameter 3cm, complete resection with clear margins 2mm, negative axillary lymph nodes or singular nodal micro-metastasis, no distant metastases, hormone receptor-positive tumours, and were >/= 35 years. Patients were excluded if mammographically they showed a multicentric invasive growth pattern, poorly differentiated tumours, residual diffuse micro-calcifications, extensive intraductal component, or vessel invasion. Median follow-up was 32 months (range; 8-68). The local control rate was 99.3% (272/274), the 3 year-local-recurrence-free survival probability, 99.6%. Peri-operative complications occurred in 5.5% (15/274): 9 (3.3%) experienced implant infection and 6 (2.2%) hematoma. Acute toxicity (Grade 1/2 radio-dermatitis) was seen in 6.6% (18/274). Late side effects >/= Grade 3 (fibrosis, telangiectasia) occurred in 1.8% (4/274). Cosmetic results were excellent/good in 94% (253/274). This analysis underlined the safety and effectiveness of APBI in a carefully selected subgroup with favourable disease characteristics. Of course, longer follow-up and randomised trials are necessary to conclusively assess the potential of APBI.