Permanent Prostate Brachytherapy

Overview

Brachytherapy treats disease by exposing tissue to a small, radioactive source (pellet or seed). In permanent prostate brachytherapy, doctors implant small radioactive pellets a short distance from cancerous tissue in the prostate. The seeds contain a radioactive isotope that emits radiation to kill cancer cells. The seeds are left in place to give off a low dose of radiation for weeks or months.

Men who have small, early stage prostate cancers may be considered for permanent prostate brachytherapy. The treatment may be used alone or in combination with radiation given outside the body or hormone therapies. Permanent prostate brachytherapy is minimally invasive and allows patients to resume most normal physical activities within days.

At Mayo Clinic, radiation oncologists use ultrasound and X-ray to guide the placement of 60 to 120 rice-sized radioactive seeds into the prostate. People are under general or spinal anesthesia, generally for two hours or less, while doctors place the seeds.

Temporary high dose implants

Prostate brachytherapy may also be performed with temporary high dose rate implants. People who receive high dose implants don't require special precautions for radiation exposure, because no radioactive sources are left in place after the procedure.

Results

Mayo Clinic researchers investigate advanced therapies to determine their potential for treatment of cancer. Studies conducted at Mayo Clinic report that:

• Of patients who were appropriate candidates for radiation seed therapy, 90 percent remained free from prostate cancer for at least five years
• In people followed for 10 or more years, cancer was controlled in more than 85 percent of those treated with permanent prostate brachytherapy

Some people experience frequent urination, burning with urination, urinary urgency or a weakened urine stream after treatment. These symptoms may last several months. A doctor can prescribe medication to help if the symptoms persist. Continued improvement in permanent prostate brachytherapy techniques has improved results while limiting rates of urinary, bowel and sexual dysfunction.

Safety

Permanent prostate brachytherapy uses low-energy radioactive sources. The majority of the radiation that seeds emit is delivered within an inch of the seed.

Once the seeds are in place, the radiation emitted to tissues around the prostate and to other people is minimal. People who have received permanent prostate brachytherapy, however, should follow several radiation safety precautions, including:

• Limit prolonged close contact (less than six feet) with children and women who are or may be pregnant for two months after the implant.
• Avoid letting children sit on the recipient's lap for prolonged periods for two months after the implant.
• Flush down the toilet any seeds that are passed during urination within the first few weeks after the implant.
• Avoid sexual intercourse for two weeks after the implant. A seed may be passed during ejaculation, so men should wear a condom during sex for two months after the implant.

The Mayo Clinic Cancer Center offers opportunities to enroll in cancer research studies, receive treatments in development and actively participate in treatment decisions.