Breast brachytherapy: North American experience.

Accelerated partial breast irradiation (APBI) has been investigated for over a decade as a potential alternative adjuvant treatment approach after lumpectomy for women with early-stage breast cancer. The rationale for APBI is based on pathologic data regarding the spread of cancer within the breast and study of the patterns of in-breast recurrence after breast-conserving therapy performed with or without whole-breast irradiation. This report reviews the North American experience using interstitial brachytherapy for APBI. Studies achieving low failure rates have universally been distinguished from those with high failure rates by requiring documented microscopically negative surgical margins, using a target definition consisting of the lumpectomy cavity plus a 1- to 2-cm margin, and having a rigorous quality assurance program to assure target coverage. We conclude that APBI brachytherapy programs that include all of these components have great potential to overcome many of the barriers that have prevented women from pursuing standard breast-conserving therapy.