Brachytherapy Treatment for Breast Cancer
Brachytherapy refers to radiation therapy that involves placing radioactive material directly into or adjacent to the tumor, rather than through external beams. Today, brachytherapy is a standard technique in the treatment of a large number of malignancies and often used in combination with EBRT. Brachytherapy treatments use radioactive materials such as cesium-137, iridium-192, palladium-103, or iodine-125. Radioactive sources that deliver radiation at a high dose rate such as iridium-192 are referred to as HDR (high dose radiation therapy). Through the use of brachytherapy, the radioactive source can be placed next to or directly into the tumor. Because the energy of the radioactive source is low, a high energy is delivered to the tumor, with nearby normal surrounding tissues receiving very little dose. Brachytherapy can be administered using a multitude of techniques- all dependent on the tumor being treated.
Brachytherapy for breast cancer involves placing radioactive material (iridium-192) in the area where breast cancer has been removed from the breast. After breast lump removal, there is a cavity where the cancer was removed. A treatment device (SAVI applicator) is placed in the tumor cavity. The SAVI device is a balloon-like apparatus that holds a catheter with channels attached to it. The balloon-like portion of the applicator is placed into the tumor bed while the catheter portion extends out of the patient's body. The radiation sources travels through the catheter and through the channels, pausing at predetermined spots to deliver the prescribed dose to the tumor bed. The treatment device remains in place for about a week, with treatment being delivered twice a day (once in the morning and once in the afternoon) for five consecutive days. After the final treatment the device is removed. Treatment is delivered in a specially designed suite.