Unlike treatment with external radiation beam, brachytherapy is a process whereby a radioactive source is placed in the tumor itself, giving a high radiation dose to the tumor while reducing the radiation exposure to the surrounding healthy tissues. This procedure is especially beneficial for the treatment of gynecologic cancers, breast cancer and prostate cancer, which may allow some patients to avoid the removal of the involved organ.
This procedure delivers radiation directly to the area where a breast tumor has been surgically removed in a select population of patients. Breast HDR consists of a balloon catheter that is inserted into the area of the breast where the tumor was removed. Once inserted, the balloon is expanded and radiation is delivered twice a day through a tiny radioactive bead attached to a wire that is placed into the middle of the balloon.
This exposes the area surrounding the cavity with radiation. After a series of treatments are completed, the catheter is removed. The treatment allows selected patients to reduce the standard course of up to six-seven weeks of daily radiation with a treatment course that only requires one week to complete.
In gynecologic cancers, radioactive implants are a very important part of treatment, and it is common for this type of radiation to be used as part of a patient’s radiotherapy treatment course. Other names for this type of treatment are brachytherapy, internal radiation therapy, interstitial implants or intracavitary radiotherapy.
Usually, the radiation source is placed inside the cancerous area for short periods of time using various devices placed in or around the gynecologic organs, sometimes with anesthesia given to the patient, and then removed after the dose is delivered. More than one implant may be required to get the dose necessary to treat the cancer. Brachytherapy can be done alone or in combination with external radiation therapy for GYN cancers.
Small metal pellets, often called “seeds” which are radioactive, are inserted directly into the prostate gland with needles placed into the perineum (the skin right in front of the anal area) while the patient is under anesthesia. The seeds, typically an isotope of iodine or palladium, are temporarily radioactive over a few months and deliver the radiation to the prostate over this time.
After losing their radioactivity, the seeds remain in the prostate, and are harmless. This is done as a single procedure, occasionally with a short five- week course of external beam treatment depending on the disease characteristics. The procedure takes about 1.5 hours, with 2-3 hours of recovery time before discharge. A catheter is placed into the bladder at the end of the procedure, and is usually left in place 1-3 days before removal by the doctor.
This is similar to the prostate LDR implants described above, except that no radioactivity is left in the patient. Needles are inserted under anesthesia, but instead of placing radioactive pellets that deliver the treatment over a few months, the needles are used to guide a single very high activity source to the prostate to deliver the dose in a few minutes. Since this gives such a high dose at one time, the treatment is generally broken up into two separate implants, about a month to six weeks apart.
The placement of the needles, and the treatment administration, takes about three hours. There is a 2-3 hour recovery period. Prior to discharge, a catheter is placed into the bladder, and is left in place 1-3 days before removal by the doctor. At Levine Cancer Institute, this therapy is used for patients with higher risk disease, combined with a short five-week course of external beam radiation.