Prostate cancer is the leading cancer in males. Thankfully, most instances of this age-related illness are not fatal and are amenable to early diagnosis and treatment. Most physicians dealing with this problem are walking a fine line between (1) whether to treat the patient, (2) how to treat the patient, and (3) how to balance the treatment, particularly as it occurs frequently in an elderly population.

Radiation oncologists may find the decision a little easier than a surgeon might. Why? Radiation oncology uses the most advanced technology in the field, has a very low complication rate, is easy for the patient to undergo, and produces cure rates similar to those of surgery.

Since the patient risks less in terms of serious morbidity, the radiation oncologist can be slightly less concerned about the issue of over-treatment. Therefore, after hearing the pros and cons of treatment, the majority of prostate cancer patients who seek a consult usually decide in favor of potentially curative therapy using external beam radiation or seed implant therapy¹.

Prostate cancer patients who have a biopsy-positive cancer are ranked by a number of factors, including the grade of the cancer under the microscope (Gleason's Grade), the level of the prostate-specific antigen (PSA) blood test, the density of the PSA blood test, the percent of free PSA, the percent of the prostate gland involved with the cancer, the multi-centric nature of the tumor, whether the cancer is felt by the examiner, and finally, the likelihood that the cancer extends outside the prostate gland (Partin Tables).

Once these factors have been determined, the patient is presented with an estimate of the aggressiveness of the cancer and the likelihood of cancer extension outside the prostate gland. That information, coupled with the age and general health status of the patient, determines the recommended treatment plan. The radiation oncologist must then decide whether to pursue aggressive local therapy of the prostate gland, and whether to add a hormone blocking agent, and in what order. Hormone-blocking agents are used for intermediate and high-risk patients for varying lengths of time.

Radiation therapy is administered in two ways. First, a linear accelerator delivers external beam therapy over approximately 40-42 treatments, using highly targeted therapy, in order to spare most of the bladder, rectum and other pelvic structures from the highest dose of radiation. There is also a technique called intensity-modulated radiation therapy (IMRT) that approaches the prostate from many angles and many different field shapes. IMRT is a dynamic and highly precise treatment. Marker seeds are placed in the prostate to guide the oncologist even more precisely, which helps in case the prostate moves during the treatment. A small margin of normal tissue around the prostate gland is treated as well.

The other non-surgical option is a prostate seed implant, reserved for the lowest grade tumors and in patients who qualify for a treatment that treats only the prostate gland and small margin around the gland. This is done by placing 60-80 radioactive seeds in the prostate while the patient is anesthetized in a surgical center.

Most patients do very well with a prostate seed implant. The usual result is a PSA that declines dramatically, and remains down for the rest of the patient's life. Some patients will have a failure of control of the PSA at some point in the future; it all depends on the aggressiveness of the cancer. Even when that happens, however, the local disease in the prostate is generally controlled, and there are other measures that can be used to manage the PSA elevation.

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¹This statement is based on the patients who seek a consult at Dr. Gilbert's cancer treatment center, the Ben Schaeffer Cancer Institute, in Lodi, California.