Purpose: To evaluate overall survival, local tumor control and cosmetic outcome after breast-conserving surgery followed by radiotherapy without boost irradiation.
Patients and methods: In a retrospective study 270 breast cancer patients were treated with breast conserving surgery combined with a homogenous radiation of the tumor bearing breast up to a total dose of 56 Gy without local boost irradiation. Mean follow-up was 48 months. Local tumor control, side effects, cosmetic results and contentment with treatment were assessed using physical examinations and interviews based on a standardized questionnaire.
Results: Cause-specific survival at 5 years after treatment was 88.3%, actuarial disease-free survival at 5 years was 76.1%. Within 23 to 78 months after treatment 12 patients suffered from ipsilateral breast recurrence. The actuarial freedom from local recurrence (single tumor manifestation) was 96.8% at 5 years after treatment, 89% at 10 years. The occurrence of local failures was not significantly correlated to tumor size, margins, grading, nodal status, age or lymphangiosis. 15.6% of the patients developed distant metastases. In all patients treatment was performed without interruption. Side effects were predominantly of mild degree, no severe side effects were detected. 73% of physicians and 81% of patients scored their cosmetic outcome as excellent or good. 93% of patients would again decide in favor of this procedure. Whereas use of adjuvant chemotherapy as well as subcutaneous reconstruction of breast tissue did not significantly affect breast cosmesis, analysis demonstrated impaired cosmetic results related to a larger breast size.
Conclusion: The data of this study show that tumor control achieved by breast conserving surgery in combination with a radiation technique up to a total dose of 56 Gy which omits boost irradiation is within the range of literature data. Side effects of the therapy were tolerable. The treatment displayed a good compatibility with tolerable side effects and good cosmetic results.