“Should men get PSA tests to screen for prostate cancer?”
The Wall Street Journal posed the question in an informal, online poll last September. An accompanying article featured a debate between Richard Ablin, who'd discovered the prostate-specific antigen (PSA) in 1970, and an oncologist, Oliver Sartor. Ablin argued that the PSA test should be used only to screen men with a family history or active symptoms. For all other men, he said, a coin toss would be as effective. Sartor countered that the test finds cancers that can be treated early, acknowledging that for most men surveillance instead of active treatment is appropriate. Ablin retorted, “If we really could determine which cancers need treatment and which don't, we wouldn't be having this debate.”
Figure. Richard Selo...Image Tools
It appears that Sartor won: the poll showed more than 60% of readers in favor of the PSA test.
Such debates have been going on for years, but the controversy deepened last year when the U.S. Preventive Services Task Force (USPSTF) recommended that the PSA test no longer be used in primary care to screen for prostate cancer in asymptomatic men. (The task force did not evaluate the digital rectal exam, nor does its recommendation apply to men with diagnosed prostate cancer.) The task force assessed the available evidence and concluded that PSA screening at best saves one life in every 1,000 men screened and that the prevalence of false-positive results and the harms of subsequent testing and treatment of often slow-growing cancers—bleeding, pain, bowel and bladder incontinence, and erectile dysfunction among them—do not outweigh the benefits. They gave PSA screening a “D,” the lowest grade, while emphasizing that the recommendation “does not preclude discussions between clinicians and patients to promote informed decision making that supports personal values and preferences.”
But the resulting dissent among clinicians may be leaving patients without a clear sense of what their own preferences should be. The American Association of Clinical Urologists claimed that the USPSTF based its recommendation on studies that were “poor quality,” “flawed,” and “contradictory,” asserting that urologists and oncologists should have been on the task force. The American Society of Clinical Oncology reviewed 2011 data and in the August 20, 2012, issue of the Journal of Clinical Oncology recommended that men who are expected to live longer than 10 years discuss with their physicians the pros and cons of PSA testing (“there is some evidence to suggest screening is beneficial for some groups of men”). And the National Medical Association, representing African American physicians and patients, strongly opposed the USPSTF's recommendation because African American men have a 60% higher incidence of prostate cancer than white men and twice the rate of deaths from it.
One of two nurses on the USPSTF panel involved in the PSA screening recommendation, Adelita Cantu, assistant professor in nursing at the University of Texas Health Science Center at San Antonio, said that although the task force had to remain mindful of the powerful emotions that can dictate the public discourse on cancer screening, they arrived at a consensus solely on the basis of the available scientific evidence.
“Of course, science can be interpreted by whoever is reading it,” said Cantu. “Urologists may see it differently than primary care providers. At the primary care level the benefit does not outweigh the harm, but urologists may have a different way of interpreting the evidence. In the end we have to respect patients’ values while not hiding the facts of what the science says.”
The USPSTF recommends “shared decision making,” a buzzword that along with “patient-centered care” and “evidence-based practice” may present as many challenges in routine practice as it does solutions. (See Supporting Shared Decision Making for Prostate Cancer Screening.) Nursing may be particularly poised to meet these challenges. In one recently developed role, the oncology nurse navigator, a nurse works with the patient and family members and an interdisciplinary team “to allow for timely cancer screening, diagnosis, [and] treatment,” as well as “increased supportive care,” according to the National Coalition of Oncology Nurse Navigators.
The navigator makes appointments, answers questions on treatment harms and benefits, tracks down specialists, and provides emotional support for what is often a frightening and confusing ordeal. The American College of Surgeons’ Commission on Cancer, which accredits most hospitals that treat cancer, requires facilities to employ such a navigator, either a nurse or layperson, to assist each patient. (For more on the oncology nurse navigator role, see the National Cancer Institute video at http://youtu.be/R54urHEH558.)
Juli Aistars had been an advanced practice radiation oncology nurse when her facility made her the prostate nurse navigator at Northwest Community Hospital in Arlington Heights, Illinois, in 2007. At the time, she said, there were only three prostate nurse navigators in the country; now there are many more. As a navigator, she has had opportunities to educate patients, families, and other clinicians on the implications of the USPSTF recommendation against PSA screening.
“The problem with prostate cancer is that we don't yet have a test to show the difference between a slow-growing and a fast-growing cancer,” Aistars told AJN recently. “We're overdiagnosing.” In other words, the PSA isn't a precise diagnostic tool. An elevated level doesn't necessarily indicate the presence of cancer; it can also be a reaction to prostatitis. When a patient's PSA level is high, the navigator must work with the patient and physician, assessing personal and family history, as well as other risk factors, to determine whether a biopsy, surveillance, or watchful waiting is the best approach.
The issue of overdiagnosis and overtreatment has received a lot of attention lately. Pollack and colleagues reported in the November 15, 2012, issue of the journal Cancer that three-quarters of primary care providers surveyed said they offered annual PSA testing despite recommendations against it because “My patients expect me to”; two-thirds said they offer it because “It takes more time to explain why I am not screening than to just continue screening.”
As Tim Wilt, a member of the USPSTF, said in an online interview on overdiagnosis, “We want to do what we can to reduce the harms related to cancer. But in that quest we cannot be turning healthy people into sick individuals. Screening sometimes does that.” (Go to http://bit.ly/UjIlNm for the video.)
As researchers try to identify genetic and other biomarkers that can improve the detection and treatment of prostate cancer, the second highest cause of cancer death in men, individual patients, providers, and institutions are left to grapple with the decision of whether to use the PSA test at all. Aistars said that her hospital recently held its last PSA screening that was open to the public. Cantu would no doubt approve. As she said, “Prostate cancer is a bad disease, but using a poor test doesn't make it any better.”—Joy Jacobson
Supporting Shared Decision Making for Prostate Cancer Screening
Although there aren't precise definitions of and guidelines on prostate cancer screening to steer clinicians, many institutions support the idea of shared decision making. Shared decision making involves more than just the provision of information; it requires both clinicians and patients to be involved in decisions. Younger patients are more open to this than older patients are, Clark and colleagues found in an October 2009 literature review in the Open Nursing Journal, and nurses need specialized training to be effective in helping patients make shared choices.
But how effective is it? Sheridan and colleagues analyzed two randomized trials on shared decision making for prostate cancer screening (published online in November in BMC Medical Informatics and Decision Making) and found that although shared decision making interventions increased men's awareness that screening should be a shared decision, it didn't increase their participation in such decisions. Further research will help to clarify how to tailor decision aids for a variety of patients. The following resources may be of use to nurses when helping men decide whether or not to have the PSA test:
The Centers for Disease Control and Prevention has several booklets available online to help men between the ages of 50 and 74 decide whether to undergo prostate cancer screening, with publications targeting African Americans and Spanish speakers in that age group (http://1.usa.gov/RpFwft).
* The Informed Medical Decisions Foundation offers a decision aid, Deciding if the PSA Test Is Right for You, available as a DVD, a booklet in English or Spanish, or an online program (http://bit.ly/Zfig7b).
* The National Cancer Institute presents online guides on prostate cancer screening for patients (http://1.usa.gov/TzB3GZ) and providers (http://1.usa.gov/WMHMDg).
* The USPSTF provides a reader-friendly explanation of its recommendation against PSA screening (http://bit.ly/RNpwUh).
* The Mayo Clinic offers charts featuring the pros and cons of PSA screening and a summary of various recommendations from professional organizations (http://mayocl.in/VTWzuy).
* The American Society of Clinical Oncology decision aid on PSA screening includes graphics illustrating data on the risks and benefits of screening and treatment (http://bit.ly/PNM5dA).
© 2013 Lippincott Williams & Wilkins, Inc.