Brachytherapy, sometimes also called internal radiation therapy, is a type of radiation therapy for treating cancer. The procedure involves placing small radioactive implants inside the body, in or near the tumor. The different kinds of implants are called pellets, seeds, ribbons, wires, needles, capsules, balloons, or tubes.
The local radiation damages the DNA of the cancer cells and harms as few healthy cells as possible. Brachytherapy is generally used for prostate cancer. It is also used to treat gynecologic cancers as well as breast, lung and rectal cancers, cancers of the head and neck, eye cancer, and skin cancer. During the procedure, the radiation therapy team may use a needle or catheter to place the encapsulated radioactive material directly on or near the tumor. They usually use imaging techniques to guide the devices into place and position them in the most-effective locations. Occasionally, the radiation team inserts the radioactive material in a body cavity or a cavity created by surgery. There are three main types of brachytherapy:
- High-dose-rate (HDR) implants: the radiation team inserts a few tubes into or near the tumor. They leave the radiation source in place for a short period and then take them out: 10 to 20 minutes at a time. The patient undergoes one or two sessions a day for a few days or weeks.
- Low-dose-rate (LDR) implants: the radiation team inserts radiation source that remains within or next to the tumor for an elongated time. The implants are releasing a constant low dose of radiation over time (from 1 to 7 days). The patient usually needs to stay hospitalized during this time.
- Permanent implants: the radiation team inserts tiny seeds containing radiation in or near the tumor. The procedure takes about an hour and usually does not require an overnight stay in the hospital. The seeds are permanent, but the radiation gets weaker over time. Eventually, almost all the radiation will go away. Side effects of brachytherapy are usually localized and may include: swelling, bruising, bleeding, discomfort, or even pain at the radiation spot. When treating gynecologic cancers or prostate cancer, brachytherapy can lead to urinary and lower colon problems. Prostate brachytherapy might cause erectile dysfunction.