Other IORT techniques

BRACHITHERAPY involves the insertion of the radioactive compound (usually 15-30 wires of iridium 192 at high-level waste) directly into the tumor bed. Surgery can be performed simultaneously or in a second moment. Compared to external beam radiation, brachytherapy has the advantage of reducing hospitalization time and significantly lowers the side effects. The implantation of the radioactive compound takes one or two hours and usually requires one day recovery time. The pain and discomfort associated to the treatment are usually reduced and last a few days. Brachytherapy is a focal treatment: it destroys the DNA contained within cancer cells. Without DNA, cells are unable to divide and multiply, leading to tumor reduction. Patients with small tumors and localized breast or prostate cancer are candidates for brachytherapy. This technique is associated with surgery of the prostate and resulting in a lower incidence of impotence and incontinence.

MAMMOSITE is an alternative brachytherapy technique consisting of a balloon catheter that is inserted in the tumor bed during surgery after the breast cancer tumor is removed (lumpectomy). The balloon is “inflated” with saline solution so that it fits snugly into the cavity. It remains inflated during the 5-day treatment. A small portion of the catheter remains outside the breast; this is secured to a cushioned gauze pad to prevent movement of the catheter. During therapy, the portion of the catheter that remains outside the breast is connected to a computer-controlled High Dose Rate (HDR) machine that inserts a radiation “seed” to deliver the therapy. The seed is removed and the catheter unplugged once therapy is complete, usually after 5 days. REMOTE AFTERLOADING THERAPY is another technique of intraoperative radiation therapy. In this approach multiple catheters irradiate the tumor bed after excision with 20 Gy delivered by a source of iridium at 1 cm from the surface of the applicator. The applicator is immediately removed after the irradiation. The actual treatment takes only minutes, and the entire procedure lasts a couple of hours from start to finish. Typically, three treatments are given during a day and a half time period.

INTRABEAM X-ray is another variant of IORT. This technique utilizes low-energy X -photons (50 KV), which are delivered to the surgical area through spherical applicators of variable size. The treatment lasts about 30 minutes and may be associated with external radiation therapy or chemotherapy.