Perioperative high-dose-rate interstitial brachytherapy boost for patients with early breast cancer

Abstract

Aims and background

To evaluate the clinical results of perioperative high-dose-rate interstitial brachytherapy boost treatment preceding whole breast external beam radiation therapy in patients with early breast cancer.

Methods and study design

From 2005–2010, 100 patients with early breast cancer who met the eligibility criteria were enrolled in the study. Brachytherapy implant was performed during the breast-conserving surgery procedure. The boost treatment was started on the 3rd postoperative day to deliver a dose of 15 Gy in 6 fractions over 3 days. Three weeks later, external beam radiation therapy to the whole breast was started for a prescription dose of 50 Gy. The study end points were local recurrence, acute toxicity and cosmetic outcome.

Results

Median age of the patients was 46 years, and median follow-up was 52 months. No patient developed a local recurrence but 5 patients developed distant metastases. The 5-year overall survival and disease-free survival were 86% and 77%, respectively. Eleven patients had acute toxicity; 4 wound complications and 7 grade III skin toxicity. Nine of the 11 patients had breast size of more than 1500 cc. Except for the breast volume (>1500 cc), there was no statistically significant correlation between any of the patient or dosimetry-related factors and acute toxicity. Good-excellent cosmesis was observed in 87% of patients.

Conclusions

Perioperative high-dose-rate interstitial brachytherapy boost followed by whole breast external beam radiation therapy provides excellent local control, acceptable acute toxicity and good-excellent breast cosmesis in patients with early breast cancer.