Dr. Ian M. Thompson
Dr. Chris C. Parker
According to Jeanny B. Aragon-Ching, MD, FACP, of Inova Schar Cancer Institute, in Fairfax, Virginia, this discrepancy may be explained by the lack of guidelines standardizing the practice of active surveillance in the United States, outside of ASCO’s endorsement of a Canadian guideline of the practice in 2016,1 and by the limited research on patient outcomes on active surveillance.
“U.S. providers, in general, want to see more data,” Dr. Aragon-Ching said. “Even with the ProtecT trial reporting 10-year follow-up data, 10 years may not be long enough to evaluate outcomes in prostate cancer. Until providers see more data to solidify the perception that active surveillance is truly safe, it may take time for people to be convinced.”
In comparison, in the United Kingdom, active surveillance is supported by National Health Service guidelines, several U.K.-led studies, oncologists, and patients with prostate cancer.
“Active surveillance is a standard option for men with low-risk localized prostate cancer in the United Kingdom,” Dr. Parker said. “It is well established, having been commonly used for many years.”
Active Surveillance in the United States
Active surveillance has been used in the United States since the 1980s, when Dr. Thompson estimates that approximately 5% of men with prostate cancer chose it as their disease-management option. He sees the active surveillance evolution as directly related to a “eureka moment” with unintended consequences: PSA tests were developed to more efficiently diagnose prostate cancer, including low-risk tumors that might never become metastatic disease.
Treating these low-risk tumors with surgery and radiation led to myriad issues including overdiagnosis and overtreatment of prostate cancer, which costs the U.S. health care system about $58.7 million per year,2 and it also exposed patients to unwanted side effects such as sexual dysfunction and incontinence.
In response, clinicians started to recommend active surveillance for patients with low-risk prostate cancers. But when a patient’s family hears the word “cancer,” especially in the United States, Dr. Thompson said they want to actively treat it with surgery or radiation.
“Imagine a man walks into your office. You tell him he has cancer, but that active surveillance is an option. He initially leans in that direction, but his family calls up the next week and asks why if Dad has cancer, you aren’t doing something about it,” Dr. Thompson said.
Dr. Jeanny B. Aragon-Ching
“Active surveillance is here to stay unless we can find other means of treating men with low-risk prostate cancer that is going to give us the same result with lesser toxicity,” Dr. Aragon-Ching said.
But regarding whether active surveillance reaches an equilibrium with active treatment in the United States, Dr. Thompson said that emerging research in biomarkers and MRIs as diagnostic tools might be more of a determining factor in whether overtreatment of prostate cancer continues to be a problem.
“The use of MRI is changing everything. MRI can see potential lesions, prompting biopsies that may be reassigning low-risk cancers to higher-risk categories, leading to active treatment,” Dr. Thompson said. “We might see a resurgence in treatment in low-risk cancers because of these new tests, simply because these tests may result in more biopsies.”
Active Surveillance in the United Kingdom
Dr. Caroline Moore
Caroline Moore, MD, FRCS (Urol), of University College London, added that the structure of the British hospital system also impacts active surveillance, as there are clear guidelines that govern its practice and no direct financial incentives for clinicians or patients to choose one treatment over the other.
“I think it’s a number of factors. The way the health system is set up is quite helpful. There are no financial or work incentives for people to have one treatment over another,” Dr. Moore said. “There is little fear of litigation in using active surveillance, and that fear of litigation can drive treatment in other places.”
Although the active surveillance rates in the United Kingdom are already high, Dr. Moore believes they will continue to rise because of National Health Service guidelines that recommend the use of multiparametric MRIs to diagnose prostate cancer, coupled with new data from the PROMIS study.3
“The PROMIS trial results reported at the ASCO Annual Meeting in May were very positive for MRI,” Dr. Moore said.
“The recent results of the PROMIS study indicate that multiparametric MRI may be used as a triage test to decide which men can safely avoid diagnostic prostate biopsy,” Dr. Parker said. “Among men referred with a raised PSA in PROMIS, MRI could have [enabled] 27% [to avoid the need for biopsy], thus reducing the diagnosis, and hence the treatment, of insignificant cancer.”
These new MRI tests will allow clinicians and patients to determine whether yearly biopsies are needed at all.
“Typically, men undergo MRI every 2 years, and repeat biopsies or curative treatment are only done if there is clear evidence of disease progression on MRI,” Dr. Parker explained. “Most U.K. clinicians place much less emphasis on PSA kinetics.”
For more information on how the United States’ practice of active surveillance compares with other countries, plan to attend the General Session “Active Surveillance for Prostate Cancer” on February 16 at the Genitourinary Cancers Symposium. There, Laurence Klotz, MD, FRCS, of Sunnybrook Health Sciences Centre, University of Toronto, will discuss “Canadian Versus U.S. Guidelines on Active Surveillance.”