Accelerated partial breast irradiation (APBI) is a breast radiation therapy in which focused radiation is delivered specifically to the part of the breast where the tumor was removed. This localized form of radiation treatment (brachytherapy) involves the insertion of a radioactive "seed" to kill breast cancer cells that may remain after lumpectomy surgery. This procedure delivers a highly effective dose of radiation while greatly reducing treatment time. APBI is given twice a day over a period of 5 to 7 days, each treatment takes only 5 to 15 minutes, and the radiation dose is concentrated to the tissue surrounding the lumpectomy cavity, sparing normal tissue and critical organs from unnecessary radiation.
A catheter with a balloon at the tip is temporarily placed into the cavity where the tumor was removed and after surgery, the radiation oncologist sends a radioactive seed directly to the tumor site through the catheter. The catheter remains in place for the entire treatment period. No radiation remains in the body between treatments or after the final treatment. At the end of the last treatment, the balloon is deflated and the catheter is removed. This procedure is done on an outpatient basis.