'Watchful Waiting' Often Best Strategy for Slow-Moving Prostate Cancer

21 june 2010-- For patients with prostate cancer that has a low risk of progression, active surveillance, also known as "watchful waiting," may be a suitable treatment option, according to a large-scale study from Sweden.

The issue of how (or whether) to treat localized prostate cancer is controversial because, especially for older men, the tumor may not progress far enough to cause real trouble during their remaining expected lifespan. In those cases, deferring treatment until there are signs of disease progression may be the better option.

The researchers looked at almost 6,900 patients from the National Prostate Cancer Registry Sweden, age 70 or younger, who had localized prostate cancer and a low or intermediate risk that the cancer would progress. From 1997 through December 2002, over 2,000 patients were assigned to active surveillance, close to 3,400 underwent radical prostatectomy (removal of the prostate and some surrounding tissue), and more than 1,400 received radiation therapy.

After a median follow-up of just over 8 years, the surveillance group had a much higher death rate from causes other than prostate cancer -- 19.2 percent, compared with 6.8 percent in the prostatectomy group and 10.9 percent in the radiation therapy group.

This suggests that patients with a shorter life expectancy were more often selected for active surveillance rather than surgery or radiation therapy, the researchers said.

The patients who underwent surgery for prostate cancer had a lower risk of dying from prostate cancer than those in the active surveillance group. However, the difference in absolute risk of patients dying from prostate cancer was very small -- only 1.2 percent after 10 years of follow-up.

The researchers concluded that, based on these findings, active surveillance is the best strategy for many patients with low-risk prostate cancer.

"With a 10-year prostate cancer-specific mortality of less than three percent for patients with low-risk prostate cancer on surveillance, this strategy appears to be suitable for many of these men," wrote Dr. Par Stattin, of Umea University, and colleagues.

The study was published online June 18 in the Journal of the National Cancer Institute.