Prostate Cancer: Interstitial Brachytherapy

Cross section of a prostate showing radioactive seeds for interstitial brachytherapy.

Radiation therapy is one way to destroy cancer cells. Cancer cells die for months after the therapy ends. Radiation can be given from outside or from inside the body. Radiation given from inside the prostate gland is called internal radiation. It’s also known as interstitial brachytherapy.

How it works

During this therapy, sources of radiation are put inside the prostate. Tiny metal seeds are used. They are about the size of a grain of rice. The seeds can be left in place permanently. Or they may be removed later. The benefit of this kind of treatment is that the radiation is limited to a small area. It does not affect the whole body.

Possible risks and complications

All procedures have risks. Most risks from this procedure are related to organs that are near the prostate and may be affected by the radiation. The risks include:

  • Bowel problems

  • Blood in the urine or semen for a short time after treatment

  • Bleeding or inflammation of the bladder or rectum

  • Burning feeling when urinating

  • Erectile dysfunction

  • Loss of bladder or bowel control (incontinence)

  • Movement of seeds out of prostate

  • Needing to urinate often

  • Pain, bruising, or swelling where the needles were inserted

  • Urinary obstruction

Before treatment

You may be given hormone therapy to shrink the prostate. An ultrasound, CT scan, or an MRI is then used to map the size and shape of the prostate.

During treatment

You are given anesthesia to keep you free from pain during the procedure. You will have one of these 2 treatments:

  • Permanent seeds. Permanent seeds are known as low dose rate (LDR) brachytherapy. LDR can be done during an outpatient visit. This means you can go home the same day. The healthcare provider uses a needle to put tiny radioactive seeds into the prostate gland. The needle is guided using images from a transrectal ultrasound.

  • Temporary seeds. Temporary seeds release a single high dose of radiation (HDR). The healthcare provider puts small tubes (catheters) into the prostate gland. The catheters are hooked up to a machine. The machine sends strong radioactive sources into the prostate for several minutes at a time and then removes them. This is done a few times. The catheters are removed after the last treatment. You may need to stay in the hospital for 1 to 2 days during this treatment. The permanent brachytherapy procedure takes about 1 to 2 hours.

After treatment

Soon after treatment, you can resume your normal activities. Your healthcare team will help you to manage any side effects. With permanent seeds, you may need to restrict your contact with young children and pregnant women for a period of time. You may also need to take other precautions. Talk with your healthcare team.