COMBINING SEED IMPLANTS WITH OTHER TREATMENTS

     With improvements in the ability to assess whether or not cancer has spread outside the prostate, radiation oncologists have begun to use one or more types of treatment depending on a patient’s particular circumstance. In general, the higher the risk of spread, the greater the likelihood that physicians will recommend a combination of treatments.

     At the Seattle Prostate Institute and at other brachytherapy centers, seed implants are used either alone or in combination with other forms of treatment depending on a patient‘s risk status.

     1. Seed Implants as the Only Treatment: This approach takes maximum advantage of the confined, high dose radiation that seeds can provide. The use of seeds alone is best suited for low risk patients with very early stage prostate cancer, usually defined as those with a stage T1 or T2 cancer, a Gleason score of 2-6, and a PSA level of 10 or below. The cure rate for these patients is very good and it has been our experience that there is no benefit to be gained by the addition of other therapies. Moreover, using seeds as the only treatment tends to involve the least troublesome side effects. It is clearly the most convenient and least disruptive treatment, involving only a single, 1-hour outpatient procedure. Thanks to PSA testing and the increasing awareness of the importance of early diagnosis, most of the men cared for at the Seattle Prostate Institute fall into the low risk group and receive implantation as their only treatment..
 
     2. Seeds Combined with External Beam Radiation: This combination treatment is generally recommended for intermediate and high risk patients, those with a somewhat higher chance of having cancer outside of the prostate. Generally speaking, intermediate risk patients are those with one of the following: a stage T3 cancer, a Gleason score of 7-10, or a PSA level of 10 or more. High risk patients meet two of these criteria.

     With this combination treatment, patients first undergo a 5-week course of daily external beam radiation treatments. The implant is performed 2-4 weeks after the end of the external beam therapy.

     This approach is obviously less convenient for patients and there are slightly more rectal side effects due to the external beam radiation. However, in terms of protection against the possible spread of cancer outside of the prostate, the addition of external beam therapy provides an effective dose of radiation to areas around the prostate that are beyond the reach of the radiation emitted by seeds alone.

     3. Adding Hormone Therapy: Also referred to as "hormone deprivation", "anti-androgen therapy", and "complete hormone block", this form of treatment uses chemical agents to lower the levels of testosterone in the blood. Testosterone, the male sex hormone responsible for the development of masculine characteristics, also has the effect of promoting the growth of certain prostate cancer cells. Hormonal therapy is principally used as a life-prolonging treatment for patients with metastatic prostate cancer at the time of diagnosis, or for patients whose cancer reappears following earlier attempts at cure with surgery or radiation.