Accelerated Partial Breast Irradiation (APBI) refers to the use of limited, focused RT as a more convenient alternative to conventional whole breast radiation radiation therapy (WBRT) for women following breast-conserving surgery. Compared with WBRT, APBI delivers a higher dose of RT per day to a limited volume of tissue, encompassing the lumpectomy bed with margin over a shorter period of time and leading to potentially fewer late skin and surrounding organ side effects . The results from the randomized study comparing APBI to whole breast radiation therapy have not yet been reported, however, many single institutional studies demonstrate equivalent outcomes in highly selected patients with favorable breast cancer features. Treatment options with accelerated partial breast irradiation available through our departments include:
1. Intracavitary Brachytherapy: A radiation delivery device is placed into the lumpectomy cavity. Single lumen and multi-lumen balloon catheter and non-balloon devices have all been used successfully. A radioactive source imbedded in a wire is guided into the catheter to temporarily expose the 1-2 cm radial margin beyond the cavity to the prescribed dose of radiation, taking approximately 5-10 minutes. This is repeated twice daily for 5 days, for a total of 10 fractions.
2. External beam radiation therapy (EBRT) with 3D conformal or IMRT treatment techniques: This treatment utilizes a linear accelerator-based treatment algorithm to design radiation utilizes multiple angled beams to create a dose-distribution that conforms to the 1-2 cm margin beyond the lumpectomy cavity. Similar to brachytherapy approaches, this treatment is performed twice daily for a total of 10 fractions over 5 days.
