Almost all men with early prostate cancer survive 10 years, regardless of treatment

The survival rate for early-stage prostate cancer is 99 percent after 10 years, regardless of whether men undergo surgery, radiation or are "actively monitored," according to studies published Wednesday. Researchers hailed the results as good news, saying they had been expecting a survival rate of 90 percent.

The two new studies, published in the New England Journal of Medicine, also illustrated the complicated treatment equations facing men with early-stage prostate cancer, and they immediately set off a debate among physicians about how to interpret the results.

Researchers from the Universities of Oxford and Bristol found no difference in survival rates among men who were randomly assigned to surgery, radiation or monitoring; it is the largest study of its kind. Those who underwent surgery or radiation cut in half the risk that their disease would spread to bones and lymph nodes, compared with those who were simply monitored. Although the treatment didn't extend life during the first 10 years, a survival benefit might yet emerge in the next five or 10 years, the researchers said. The scientists also found that the surgery and radiation treatments sometimes caused severe side effects, including sexual dysfunction, incontinence and bowel problems.

"Men with newly diagnosed, localized prostate cancer need to consider the critical trade-off between the short-term and long-term effects of radical treatments on urinary, bowel and sexual function and the higher risks of disease progression" that comes with monitoring, the researchers wrote.

Freddie Hamdy, a professor of surgery and urology at the University of Oxford who was the lead researcher, said his advice to patients is that they should not "rush to receive treatment, but to really digest and really look at the side effects that the treatments produce."

In an editorial that accompanied the studies, Anthony D'Amico, chief of genitourinary radiation oncology at Brigham and Women's Hospital and Dana-Farber Cancer Institute, emphasized the studies' finding that surgery and radiation reduced the risk of metastasis and disease progression. "If a man wishes to avoid metastatic prostate cancer and the side effects of its treatment, monitoring should be considered only if he has life-shortening coexisting disease" that might prevent him from living for much longer than 10 years.

But while D'Amico saw reason to be wary of monitoring, Fox Chase Cancer Center urologic oncologist Alexander Kutikov pointed out that some of the monitored men whose cancers metastacized had relatively aggressive tumors, based on the standard grading system. In the U.S., such men would not be considered good candidates for monitoring. "We're learning who is most appropriate for it," Kutikov said. "This underscores that not every man is suitable."

Two radiation oncologists - Eric Horwitz at Fox Chase Cancer Center and Neha Vapiwala at the University of Pennsylvania - were heartened to see that, contrary to many previous studies, radiation therapy had a better side effect profile than surgery in terms of urinary and sexual dysfunction.

"Patients are often told that radiation side effects will continue indefinitely and get worse," Vapiwala said. "That's not what this study shows."

For the British study, more than 82,000 men between 1999 and 2009, ages 50 to 69, were tested with a blood test called PSA, for prostate-specific antigen. About 1,600 were diagnosed with early-stage cancer and agreed to take part in the study. They were randomly assigned to one of three groups: Those who got surgery to remove the prostate, called a radical prostatectomy; those who got radiation; and those who got active monitoring, which researchers described as "less passive" than the "watchful waiting" stance used by many doctors in the United States. Researchers studied mortality rates at 10 years and whether the cancer progressed and spread; a second study addressed the impact of the treatments reported by the men.

Their conclusion was that the three approaches did not translate into "significant differences" in deaths. "Thus," they concluded, "longer-term follow-up is necessary."

Part of the conundrum facing researchers and clinicians is that prostate cancer is both overtreated and undertreated. For years, many doctors say, men were overtreated based on the results of a PSA test. The test can result in "false positives," or encourage aggressive treatment of malignancies that are so slow-growing that they aren't a threat. In many cases, men no longer get PSA tests as a routine matter.

However, men still die from prostate cancer - because doctors don't know which cases will turn into a metastatic form. More than 180,000 men in the U.S. will be diagnosed with prostate cancer this year, and more than 26,000 will die from it.

Staff writer Marie McCullough contributed to this article.