© 2005-2012 American Society of Clinical Oncology (ASCO). All rights reserved worldwide.
An analysis of data from men diagnosed with prostate cancer shows that radiation therapy after a radical prostatectomy (surgery to remove the prostate) can reduce the risk of dying from prostate cancer by more than 60%. This procedure is called salvage radiotherapy (SRT) and is most beneficial for men with rapidly rising levels of prostate-specific antigen (PSA, a protein in prostate tissue).
The researchers compared prostate cancer-specific survival (the probability of not dying from prostate cancer) of 635 men with rising PSA levels who had already been treated for prostate cancer. Of these men, 160 had received SRT alone, 78 had received SRT and hormone therapy, and 397 had received no SRT or hormone therapy.
After 10 years, 86% of men who received treatment with SRT alone and 82% of men who received treatment with SRT and hormone therapy had not died from prostate cancer, compared with 62% of men who did not receive SRT. Prostate cancer-specific survival improved only when SRT was given less than two years after a biochemical recurrence (when PSA levels start to rise after a radical prostatectomy).
The use of SRT was shown to be more effective for men with PSA levels that doubled in less than six months (a measure of more aggressive cancer), reducing the risk of dying from prostate cancer by 86%. For men whose PSA levels doubled in six months or more, SRT did not lower the risk of death, due to the fact that these men had less aggressive prostate cancer and may have fared well even without radiation therapy.
What this means for patients
“These findings are the first to support the effectiveness of salvage radiotherapy for improving survival in men with recurrent prostate cancer. If confirmed, these results suggest that for high-risk prostate cancer, radiotherapy should be given promptly when there is evidence for recurrence after radical prostatectomy, as early salvage radiotherapy may improve overall survival,” said lead author Bruce Trock, MD, Associate Professor of Urology, Epidemiology, Oncology and Environmental Health Sciences at Johns Hopkins University School of Medicine in Baltimore, Maryland.