Brachytherapy, sometimes referred to internal radiation or implants, is the placement of radioactive sources in or just next to a tumor. To position the sources accurately, special catheters or applicators are used. Because the radiation sources are placed so close to the tumor, your doctors can deliver a large dose of radiation directly to the cancer cells with far less exposure of normal tissues.
Some sources are placed permanently and remain in the body even after their radiation has been expended and they are no longer radioactive. Other sources are placed temporarily inside the body, and the radioactive sources are removed after the prescribed dose of radiation has been delivered. This can be performed manually or using a special radiation delivery machine called a remote afterloader. This machine allows the radiation to be delivered and removed without exposing the patient or clinical staff to unnecessary radiation.
There are two main types of brachytherapy: intracavity and interstitial. For intracavity treatment, the radioactive sources are put into an existing space near the tumor, such as in the uterus, the vagina or the trachea/bronchus (windpipe). For interstitial treatment, the radioactive sources are put directly into the tissues, such as the prostate.
Often these procedures require anesthesia and possibly a brief hospitalization. Patients with permanent implants may have a few restrictions at first and then can quickly return to their normal activities. Temporary implants usually are left inside of your body for a few days while you recieve treatment.
High dose rate radiation allows all radiation oncologists to complete brachytherapy quickly, in about 10 to 20 minutes. Powerful radioactive sources travel through small tubes called catheters to the tumor for the amount of time prescribed by your radiation oncologist. They stay in place, within catheters, until they deliver the desired dose and shape of radiation needed and then are withdrawn by computer control. You may be able to go home shortly after the procedure. Depending on the area treated, you may receive several treatments over a number of days or weeks.
Most patients feel little discomfort during brachytherapy. If the radioactive source is held in proper position by an applicator, you may feel discomfort from the applicator (and there are medications that can help), but the delivery of radiation is completely painless.