Research has shown that patients with early-stage breast cancer who receive accelerated partial breast irradiation (APBI) via high dose rate (HDR) implant twice daily for five days have outcomes similar to those who undergo whole breast external radiation therapy (XRT) once daily for five to six weeks in terms of breast tumor local recurrence; however, the APBI implant is associated with significant complications. Newer findings observed that APBI using non-invasive intensity modulated radiation therapy (IMRT) or stereotactic body radiation therapy (SBRT) given once daily in five fractions is not inferior to once daily six-week XRT in terms of local recurrence; IMRT/SBRT had better comparative outcomes in terms of acute and late effects, as well as cosmesis. The IMRT/SBRT study defined the clinical target volume (CTV) by the injection of individual fiducial markers on the border of the surgical cavity.
In a study presented at the San Antonio Breast Cancer Symposium, researchers sought to confirm the previous IMRT/SBRT findings but with a simpler fiducial system.
The researchers evaluated 86 patients who underwent SBRT targeted to a Biozorb-defined CTV with the surgical cavity walls sewn to the Biozorb device. Patients were eligible for inclusion if they were older than 40 years, had a tumor size of 3 cm or smaller, and had negative surgical margins and sentinel node dissections. Patients received SBRT 30 Gy in five fractions.
Median follow-up was 12 months (range, 1-24 months). At the time of publication, none of the patients presented local recurrence, and no skin reactions were reported. One case of pain around the Biozorb site was documented, which was resolved following a short course of steroids. Cosmesis was graded as “excellent” in 100% of cases by the surgeon, radiation oncologist, and nurse.