Low-kilovoltage, single-dose intraoperative radiation therapy for breast cancer: results and impact on a multidisciplinary breast cancer program.

Background: The Intrabeam (Carl Zeiss) brachytherapy device (IB) is an electronic brachytherapy device that can be used to deliver low energy x-rays (50 kV) to a lumpectomy cavity at the time of lumpectomy for breast cancer. Reported experience with IB for breast cancer in the United States has been extremely limited. Here we describe our experience and analyze the impact of IB on our multidisciplinary breast cancer program.

Study Design: This is a retrospective review of a prospectively collected breast cancer database. Patient characteristics, treatment characteristics, recurrence, and cosmesis were analyzed. Cost data were also analyzed to determine the impact of IB on the breast cancer program.

Results: Seventy-eight patients underwent 80 IB treatments in this series between November 2010 and October 2012. Most patients had invasive ductal carcinoma. Mean total operative time for patients receiving lumpectomy, sentinel node biopsy, and IB was 132 minutes (range 79 to 243 minutes). Intrabeam brachytherapy was the only adjuvant radiation required in 81% of patients, and only 15% of patients required additional operation after the index lumpectomy procedure. At 12 months of follow-up, cosmesis was good to excellent in 92% of patients. There have been no local recurrences in patients treated in this series. Intrabeam brachytherapy is associated with considerably lower costs ($1,857) than conventional whole breast radiation therapy ($9,653).

Conclusions: Implementation of IB impacts treatment planning and operating room use in a multidisciplinary breast cancer program. The safety profile, ease of administration, and reduced costs of IB favor its more widespread use in selected patients with early-stage breast cancer.