Can radiation therapy combat a rising PSA after surgery?

I had a radical prostatectomy a year ago and thought I was cured. But now my PSA is rising rapidly, making me think I have an aggressive form of prostate cancer. Is there any reason to believe that radiation therapy might help?

Carolyn Lamb, M.D., a radiation oncologist at Mount Auburn Hospital in Cambridge, Massachusetts, says:

Unfortunately, 15% to 40% of patients who undergo a radical prostatectomy experience a setback like yours within five years. Most men who find themselves in this situation have more questions than answers: Should I start salvage therapy right away or wait until I have signs of metastatic disease? If I opt for salvage therapy, should I choose radiation therapy, hormones, or a combination of the two? And no matter which way you go, there are trade-offs. Your PSA may improve, but side effects may worsen your quality of life.

A recent study may offer some guidance. Researchers at Johns Hopkins Hospital followed 635 men whose disease recurred after a radical prostatectomy. Of that number, 397 men opted for no treatment, 160 received salvage radiation therapy, and 78 combined salvage radiation therapy and hormones. The researchers found that the men who received no treatment were twice as likely to die from prostate cancer over the next six years, on average, as those who had radiation.

Physicians have believed that men like you with rapidly rising PSA scores were unlikely to benefit from radiation therapy because the cancer had probably already spread out of the local area. This study contradicts the conventional thinking: researchers found that the survival benefit was greatest for men with aggressive cancers. Among the 166 men with a PSA doubling time of less than six months, those who had radiation alone or combined with hormone therapy were 75% less likely to die of prostate cancer than men who opted for no treatment. Those who did the best started radiation within two years and when their PSA was 2 ng/ml or lower.

Admittedly, men in this study weren’t randomly assigned to receive one treatment or the other. But the findings offer some evidence that radiation therapy can extend survival. (However, having radiation therapy after a radical prostatectomy may increase the risk of complications, such as impotence and urinary incontinence.) Talk to a radiation oncologist about developing a treatment plan to meet your needs.

SOURCE: Trock BJ, Han M, Freedland SJ, et al. Prostate Cancer-Specific Survival Following Salvage Radiotherapy vs. Observation in Men with Biochemical Recurrence after Radical Prostatectomy. Journal of the American Medical Association 2008;299:2760–69. PMID: 18560003.

Originally published Oct. 1, 2008; last reviewed April 8, 2011