Patients should get:
|Very low risk|
Patients should get:
Physicians Urged to Consider Active Surveillance in Prostate Cancer
The most explicit call to date for expanding the use of active surveillance in the treatment of prostate cancer was made last week by the National Comprehensive Cancer Network (NCCN), a not-for-profit alliance of leading cancer centers. Updated guidelines from an NCCN panel urge clinicians to offer active surveillance to their patients whose prostate cancers are at low risk of progressing to life-threatening disease.
Active surveillance—in the past also called “watchful waiting” and “expectant management”—refers to a strategy of forgoing immediate treatment after a diagnosis of prostate cancer in favor of regularly scheduled testing and clinical exams to closely monitor the disease. Active surveillance can include prostate-specific antigen (PSA) testing, digital rectal exams (DRE), and prostate biopsies. If, at some point, there are indications that the disease is progressing—such as significant growth in the tumor or a rapid increase in PSA level or higher tumor grade on biopsy—definitive treatments such as surgery or radiation therapy can be pursued.
Of the more than 192,000 estimated prostate cancer cases diagnosed in 2009, about half may fall in the low-risk category, explained Dr. Bhupinder Mann from NCI’s Division of Cancer Treatment and Diagnosis.
How the NCCN Guidelines Define Low Risk
Under the updated guidelines (available online with free registration), active surveillance should be recommended to men with low-risk prostate cancer who have a life expectancy of less than 10 years. Men with low-risk cancers have a relatively low PSA level and their tumors are small, confined to one side of the prostate, and have a low tumor grade, or Gleason score (see sidebar). The guidelines also established a new category of very-low risk, or clinically insignificant prostate cancer. In men with a life expectancy of up to 20 years who fall into this new category, the guidelines recommend advising only active surveillance as the preferred management approach.
“The entire [prostate cancer] treatment committee is concerned about the overdiagnosis and overtreatment of prostate cancer,” explained the panel’s chair Dr. James L. Mohler from the Roswell Park Cancer Institute. The impetus for the update, Dr. Mohler continued, was the publication last year of results from two large clinical trials of prostate cancer screening that showed there was significant overdiagnosis and overtreatment of cancers that likely would have never been a cause for concern.
“Most men find out that they have prostate cancer and what do they want? They want it gone,” Dr. Mohler said. “There are too many men suffering the side effects of treatment, and society is bearing the costs of those treatments. And too much of it is unnecessary.”
To that point, a study published last September estimated that, since 1986, as many as 1 million men have received definitive treatment for a prostate cancer (diagnosed as a result of PSA screening) that would have never threatened their lives. Despite the concerns about overtreatment and the call to expand active surveillance, Dr. Mohler stressed that it’s still an individual decision that patients must make in consultation with their physicians.
Although there are clear benefits to active surveillance in the appropriate patients, the guidelines panel noted that choosing this treatment approach is not a simple process or decision. In addition to the need for frequent exams and tests, from a disease perspective, waiting to see if the cancer progresses could eventually mean having to treat a more aggressive tumor, with a lower likelihood of cure and a greater risk of serious side effects.
The risk of such progression, Drs. Mann and Mohler agreed, is low. According to Dr. Mohler, the risk of a significant tumor grade increase is around 5 percent, and the risk of an increase in PSA is between 16 and 25 percent.
No data have been published from randomized clinical trials directly comparing active surveillance to immediate, definitive treatment. But based on the available evidence, Dr. Mann said, “In low-risk patients, active surveillance with delayed curative intervention is an acceptable strategy.” That contention is supported by two recently published studies (here and here) which both reported equivalent long-term cancer mortality outcomes in men who opted for active surveillance compared with those who received immediate, definitive treatment. (See the cancer research highlight in this issue on a comparative effectiveness study released last week.)
Dr. Paul Godley, a medical oncologist at the University of North Carolina Lineberger Comprehensive Cancer Center, said the recommendations are overdue. However, he noted, there are still questions about active surveillance that need to be worked out, including the appropriate trigger for transitioning to definitive treatment. “I think that will still be fairly subjective based on what the patient and his physician are comfortable with,” he said.
There’s also the matter of how clinicians will react to the updated recommendations, given that immediate, definitive treatment appears to be a fairly ingrained practice. An online poll conducted January 2009 via the New England Journal of Medicine, for instance, presented a case example of a 63-year-old man with low-risk prostate cancer. Among the respondents from the United States (not all of whom were clinicians), approximately 70 percent chose either radiation therapy or surgery over active surveillance as the preferred management option.
It is unclear, Dr. Godley said, whether the recommendation “will make the trend lines change a whole lot.” But, he continued, “it may make some physicians more comfortable with doing active surveillance themselves or referring patients to a group that is using it in their low-risk patients.”