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Prostate Seed Implants

Prostate seed implants can be a particularly suitable radiotherapy option for patients diagnosed with early stage prostate cancer. The treatment is also referred to as brachytherapy, or internal radiation therapy.

How Prostate Seed Implants Work

About 100 radioactive seeds (Iodine-125) are injected into the prostate under anesthesia where they emit low levels of radiation for a few months. The procedure is usually performed on a one-time, outpatient basis and takes about two hours. The seeds are distributed into the prostate using tiny implant needles that your doctor guides using an ultrasound instrument.

Physician experience is an important parameter in the ultimate success of prostate seed implants, and doctors at the Stanford Cancer Center have significant experience with this procedure. Although the seeds eventually stop delivering radiation, they remain in the body permanently.

Benefits of Prostate Seed Implants

Fewer Side Effects
Each individual seed emits a very low level of radiation that can only penetrate a few millimeters of tissue. Therefore, surrounding structures that can be damaged by radiation (such as the bladder, urethra and rectum) are out of the seeds' emission range.

This means that you are less likely to experience side effects in these areas than with traditional radiation therapy.

The one-time procedure with a few follow-up visits is more convenient for patients than traditional radiotherapy which can require daily hospital visits for many weeks.

Precautions for Patients with Prostate Seed Implants

During the period when the seeds are emitting radiation, you should limit the amount of time children or pregnant women spend sitting on your lap to keep their radiation exposure to safe levels.

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