Many men diagnosed with prostate cancer should not undergo treatment right away, but rather, have their cancer closely monitored and treated only when the disease progresses, according to an independent panel convened by the National Institutes of Health (NIH).
The panel said men with low-risk prostate cancers, or about 100,000 men in the United States, should receive so-called active surveillance, a strategy in which patients receive regular follow-up testing with the intention of treating if the cancer becomes more aggressive.
Currently, about 10 percent of men diagnosed with prostate cancer delay treatment, and the remaining 90 percent receive treatments such as surgery or radiation therapy, according to the National Institutes of Health. Instead, about 40 percent could receive active surveillance, the panel said.
Studies show that men with low-risk prostate cancer who receive active surveillance live as long as those who receive immediate treatment.
However, it remains unclear how to best carry out active surveillance — for instance, studies have not conclusively shown how often men should receive follow-up blood tests and biopsies, and under what conditions treatments should begin. More research is needed to determine which strategies will provide the best outcomes for patients, the panel said.
"Prostate cancer affects some 30 [to] 40 percent of men over the age of 50," said Dr. Patricia Ganz, chairperson of the panel. "Some of these men will benefit from immediate treatment; others will benefit from observation. We need to standardize definitions, group patients by their risks, and conduct additional research to determine the best protocols for managing low-risk disease," Ganz said.
Low-risk prostate cancer
Treatments for prostate cancer come with risks, including erectile dysfunction and loss of urinary control. Moreover, of the 240,000 prostate cancers diagnosed this year, more than half will not be aggressive at diagnosis, and are unlikely to become life-threatening, the NIH says.
Current blood and pathology tests do an excellent job of distinguishing which cancers can be safely monitored from those that need immediate treatment, said Dr. Martin Sanda, director of the Prostate Center at Beth Israel Deaconess Medical Center in Boston, who was not involved in the panel.
The panel said there is an emerging consensus in the field regarding the criteria used to define "low-risk" prostate cancer. These include a prostate-specific antigen (PSA) level less than 10 nanograms per milliliter, and a Gleason score of 6 or less. The Gleason score grades cancers on a scale from two to 10;the the higher the score, the more aggressive the cancer.
Because the word "cancer" can produce anxiety in patients, the panel recommended a different term be used for low-risk prostate cancers identified after patients undergo PSA screening and subsequent biopsies. This approach would be similar to the use of the term "ductal carcinoma in situ," which designates the earliest form of breast cancer.
In addition, more research is needed to identify biological markers further distinguish between aggressive and nonaggressive cancers, the panel said.
Screening for prostate cancer, with PSA blood tests and possible biopsies, also comes with risks, including infections, pain and anxiety. Recently, the U.S. Preventative Task Force recommended against screening with the PSA test in healthy men, citing concerns about overtreatment.
But some doctors say active surveillance provides a middle ground between screening everyone and overtreating many, and screening no one at all.
"The [U.S. Preventative Task Force] would probably have done a better service had they considered the possibility of increased use of monitoring the lowest-risk cancers, as opposed to a blanket approach of 'let's not try to diagnose prostate cancers at all,'" Sanda said.
The idea behind active surveillance is "to have the benefit of screening while avoiding the harm of screening," Sanda said.
The choice to immediately treat or monitor prostate cancer will depend on the individual. The panel recommended doctors speak with their patients about their options.
Hopefully, the new statement "will help spread the word about active surveillance," Sanda said. "Often times when patients hear the word cancer, they assume that it's going to be treated. Having groups of physicians, scientists and health care administration have [a] consensus statement that it's safe to not treat some forms of prostate cancer could help men accept that as a care option."
Pass it on: Some men with low-risk prostate cancers will be candidates for active surveillance rather than immediate treatment, an expert panel says.