Radiation therapy has been a standard therapy for the treatment of prostate cancer for at least 30 years. Approximately 40% of all patients with prostate cancer are treated with radiation therapy.
If the patient elects to have radiation treatment, he will receive simulation and a radiation treatment planning CT scan of the prostate area. This CT scan is done in the Diagnostic Radiology Department under guidance of a specialty-trained physics staff. The data from the CT scans are then transferred to a computer system and are used to reconstruct a three-dimensional image of the tumor. This image enables doctors to design a radiation port with complete coverage of the tumor while providing maximum sparing of surrounding normal tissue.
Using a sophisticated computer program, the most optimum treatment is then generated. Also, based on three-dimensional images, a custom block will be made for each patient to spare normal tissues, such as the bladder and rectum. This technique, while lowering treatment complications as compared to conventional therapy, has shown an improved biochemical and pathological control rate with excellent survival rates.
The treatment usually takes approximately seven weeks, Monday through Friday, five days a week. Each treatment takes only ten minutes, including positioning and actual duration of exposure to radiation. During the radiation treatment, the patient will be seen at least once a week by the radiation oncologist who will monitor the progress of treatment and the possible side effects.
Results of Radiation Treatment
Radiation therapy has been a standard therapy for the treatment of prostate cancer for at least 30 years, and is covered by Medicare and private insurances. Nationwide, approximately 40% of all patients with prostate cancer are treated with radiation therapy. The results of radiation treatment, stage-by-stage, are as good as, or even better than, the results of radical prostatectomy. The American Urologic Association Prostate Cancer Guideline Panel analyzed all available data on radiation therapy and surgery and concluded that, “there was no clear-cut evidence for the superiority of any one treatment.”
The RTOG (Radiation Therapy Oncology Group) data reported that the ten-year survival rate of Stage T1b and T2 NoMo (no positive lymph nodes and no metastasis) patients treated with radiation therapy exceeds the expected survival rate of the general population where 86% are free of clinical local recurrence and 85% are free of cancer death at ten years. In terms of biochemical (PSA) control rate, the data from major medical centers show that 40 to 56% of all patients treated with radiation for all stages of cancer have non-rising PSA at five years.
A patient with early stage disease has an 80% to 90% chance of having a non-rising PSA at five years with radiation treatment, which is the same as the best surgical reports.
Short and Long-Term Side Effects of Radiation Treatment
During the radiation treatment, the patient may experience some discomfort with urination and bowel movements, due to the irritation of part of the bladder and part of the rectum. These are temporary and usually are relieved with medications. Most patients, however, continue on with their daily activities and their lifestyle is not interrupted by these reactions.
Once treatment is completed, the acute reactions resolve, usually within one to two weeks. However, long-term adverse reactions may be possible in less than 5% of patients. These include chronic proctitis and cystitis, strictures of urethra, urinary incontinence and ulceration of the rectum. Depending on the degree of chronic side effects, surgical management may be required. These severe complications are limited to less than 5% of the cases and the use of a three-dimensional treatment planning system with maximum sparing of normal tissue may further reduce this.
One of the major long-term effects of radiation treatment, which occurs in approximately half of the patients, is impotence. The chance of impotence in older patients is slightly higher. It should be noted that the risk of impotency after external beam radiation treatment is lower than that following nervesparing radical prostatectomy.