Editorials

What’s a doctor to do?

Helping patients decide about prostate cancer screening

Alan Katz, MB CHB, MSC, CCFP, FCFP    Jeffrey J. Sisler, MD, MCLSC, CCFP, FCFP

Now, if men don’t get a PSA, and then they get cancer, I have no sympathy for them. That’s just stupid on their part, they could have prevented it, but didn’t;… it’s their doctor’s fault, too—a doctor is supposed to prevent things, not ignore them!1

A little over a year ago, the Canadian Prostate Cancer Network (CPCN) launched the “Living Proof” campaign. It featured a media blitz encouraging Canadian men to “Get the Test. Save Your Life.” Canadian family physicians have contrasted this message with the evidence from the Canadian Task Force on Preventative Health Care, which assigns prostate-specific antigen (PSA) screening for prostate cancer a “D” recommendation—fair evidence to exclude the test from a periodic health examination.

Many urologists share the enthusiasm of advocacy groups, such as the CPCN, for PSA screening. In this issue of Canadian Family Physician, Pickles (pages 57 and 65) joins the Canadian Cancer Society in coming down between these two perspectives, suggesting that “men should be informed of the availability of the test and of its advantages and disadvantages and should make their own decisions about whether to be tested.” This middle-of-the-road approach makes sense in light of our current knowledge, which is ably summarized in this article. Discussing PSA testing, however, demands a lot of family physicians’ time, knowledge, and skills. How are we to address this challenge?

Beliefs hard to shake

Discussing PSA screening with patients involves their values, beliefs, and experiences. As physicians, we might be inclined to take a rational approach, emphasizing information about the qualities of PSA as a screening test and the beneficial and harmful effects of prostate biopsy and cancer treatment. Men, however, might have beliefs not easily influenced by brief office discussions.1 Fear of cancer could drive them into or away from screening. Positive or negative anecdotes from family members, friends, and celebrities are more persuasive than the information we might share. Articles in the lay press encourage women to make sure their partners request the test. A distrust of statistics, which can be made to say “anything you want them to,” is common. Those interested in screening see PSA as being part of “good prevention,” and value knowing their PSA level for its own sake, even if its usefulness is unclear.

Like our patients, our beliefs and experiences as family physicians determine our attitudes toward screening.2 Older physicians and male physicians are more likely to embrace PSA testing, as are those in community practice, rather than academic practice. Anecdotes of successes or failures of screening and subsequent treatment are powerful influences on physicians, as are patient demands for testing, which account for about one third of tests in one survey.2 Physicians believe that PSA testing is a “standard of care,” yet they also recognize that the adverse effects of treating prostate cancer could outweigh the benefits.

Tudiver et al3 have suggested a model to understand how family physicians make decisions about cancer screening when guidelines are unclear or conflict. This study highlights the importance of the patient-physician relationship and proposes that family physicians feel more able to discuss and find “common ground” on screening decisions when their relationships with patients are strong and positive.

In order to make informed decisions, patients need to be given concise, useful information in a meaningful context. This means being able to evaluate the risks and benefits for prostate screening in light of their own values. The entire September 2003 issue of the British Medical Journal was devoted to the challenges of communicating risk to patients. Paling4 had some practical suggestions:

• Avoid using descriptive terms like “common” or “rare.” These words have different meanings for different people.
• Use absolute numbers rather than relative risk, eg, of 100 men screened with PSA, 10 will have abnormal results, and of these, seven will not have prostate cancer.
• Be aware that patients find positive statements, such as “a 97 out of 100 chance of being cured” more acceptable than “a 3 out of 100 chance of dying.”
• Use visual aids to explain concepts.

Discussions of the benefits of prostate cancer screening are often confused by choosing surrogate outcomes. Members of prostate cancer support groups who advocate so strongly for universal screening see the diagnosis of occult cancer as being an outcome of interest. The more appropriate outcome of a screening program should be decreased mortality, evidence for which is still lacking. What advantage is there to searching for occult prostate cancer if the ensuing treatment has not been shown to improve quality or quantity of life? The diagnosis will have created substantial anxiety in the patient and his family, and the process of getting there could well have caused other adverse effects. This argument is countered by the “right to know” perspective, and the celebrated comment attributed to prostate cancer survivor General Norman Schwarzkopf that “…you cannot sit back and do nothing, because you’ll never have perfect intelligence on the enemy. Get on with it!”5

Seeing is believing

So how do we “get on with it?” “Decision aids” present a possible solution. Designed to give information quickly and clarify patient values, simple graphics improve patients’ understanding, allow them to be more actively involved in decision making, and allow more efficient use of physicians’ time. The Ottawa Health Decision Center is a leader in this area, and a website (http://204.187.39.28) offers an excellent compendium of these resources.6 Unfortunately, no decision aid is listed that addresses the prostate cancer screening decision.6 Information pamphlets currently available are generally inadequate due to evidence of bias or a lack of appropriate graphics (www.canadian-prostate.com). Pickles does, however, present an approach to counseling in his paper that provides some guidance.

Without effective tools, each family physician is ultimately responsible for helping patients with their screening decisions. But discussions of prostate cancer screening compete with many other preventive issues that are on our agenda, many of which have higher levels of evidence supporting them. How are we to deal with all of these during one visit? We should not feel compelled to do so. The most consistent issue we hear raised by prostate cancer support groups is the lack of time family physicians have to discuss patients’ concerns. Yet adding another 20 minutes to a man’s health examination does not sound appealing. Fee-for-service practitioners might identify with one physician in the study by Tudiver et al3: “Economics also plays a part… because it can take… half an hour to explain to a patient why you don’t want to do something. It can take two minutes to do it.”

A better approach, then, is to have certain patients return for a visit to discuss PSA screening on its own. This seems more palatable than the “Don’t ask, don’t tell” approach of some physicians who do not support screening and the pre-emptory testing without discussion adopted by others. But whom do we choose? Men without preconceived opinions on the usefulness of PSA screening are likely to benefit. It would increase their knowledge on this issue and provide the time they need to make an informed decision, while enhancing the patient-physician relationship and building trust.

Men who have undergone PSA screening and men who explicitly request the test tend to remain in the pro-screening camp regardless of subsequent counseling. Similarly, men with nihilistic beliefs about cancer screening or treatment tend to maintain their stance. There appears to be little or no value in insisting on an extra visit with these patients, apart from ensuring that those being tested understand the possibility of getting false-positive or false-negative results, and the workup that would follow positive results.

Our uncertainty about the value of PSA screening will likely abate as results of the two screening trials Pickles describes are released in the coming years. In the meantime, as in so much of clinical practice, we sit with our patients in uncertainty as to the best counsel to provide. With the scales so evenly balanced, it is reasonable to be led by the preferences of patients when they exist and to offer ourselves as resources and sounding boards when they do not.

Dr Katz is an Associate Professor in the Departments of Family Medicine and Community Health Sciences at the University of Manitoba in Winnipeg. Dr Sisler is Director of Primary Care Oncology at CancerCare Manitoba and an Associate Professor in the Department of Family Medicine at the University of Manitoba.

Correspondence to: Dr Alan Katz, Family Medical Centre, 5th Floor, 400 Tache Ave, Winnipeg, MB R2H 3E1; telephone (204) 235- 3771; fax (204) 231-2648; e-mail katz@cc.umanitoba.ca

The opinions expressed in editorials are those of the authors and do not imply endorsement by the College of Family Physicians of Canada.

References

1. Farrell MH, Murphy MA, Schneider CE. How underlying patient beliefs can affect physician-patient communication about prostate-specific antigen testing. Eff Clin Pract 2002;5(3):120-9.
2. Voss JD, Schectman JM. Prostate cancer screening practices and beliefs. J Gen Intern Med 2001;16:831-7.
3. Tudiver F, Brown JB, Medved W, Herbert C, Ritvo P, Guibert R, et al. Making decisions about cancer screening when the guidelines are unclear or conflicting. J Fam Pract 2001;50(8):682-7.
4. Paling J. Strategies to help patients understand risks. BMJ 2003;327:745-8.
5. Canadian Prostate Cancer Network. Prostate Cancer Archives [webpage]. Lakefield, Ont; 2003. Available from: http://www.cpcn.org/archives/2003_10_01.htm. Accessed 2003 Nov 5.
6. The Ottawa Health Decision Center. Available from: http://204.187.39.28. Accessed 2003 Nov 3.