Prostate Cancer Screening Rhetoric Amps Up

Metaphors Abound: 'Quicksand,' 'Mirage,' 'Goldilocks,' and More

Nick Mulcahy

February 26, 2018

In a pair of recently published papers in major cancer journals on prostate cancer screening, advocates and critics are turning to colorful and emphatic language — perhaps in the hope of exerting the power of persuasion and getting their physician audience to look at this much-discussed medical intervention with fresh eyes.

First, in a position statement, titled "Prostate Cancer Screening and the Goldilocks Principle: How Much Is Just Right?", a group of 10 US urologists conclude that they are "increasingly convinced that a 'just right' approach [to screening] on the basis of personalized shared decision making is entirely possible."

That shared decision-making refers to office visits in which physicians and patients review and discuss the harms and benefits of the prostate-specific antigen (PSA) test.

The team is optimistic that the days of large-scale overtreatment of men, which has been a hallmark of population-based screening for decades, can be a thing of the past.

Going forward, "individualized screening with [shared decision-making] is the foundation on which to build a successful program of diagnosis and treatment," write the authors, led by Izak Faiena, MD, from the University of California, Los Angeles.

What's needed is a "balanced approach" to the early detection of prostate cancer, says the team, which includes high-profile urologists, such as David Penson, MD, from Vanderbilt University in Nashville, Tennessee; Matthew Cooperberg, MD, from the University of California, San Francisco; and Maha Hussain, MD, from the University of Michigan in Ann Arbor.

That approach also includes "precision-based strategies, and appropriate risk-based management for men diagnosed with prostate cancer," they say, referring to, among other things, the use of active surveillance as an initial treatment option in men with low-risk disease.

The new position statement was published online February 5 in the Journal of Clinical Oncology.

Experts interviewed by Medscape Medical News were wary of the position statement, offering comments that ranged from critical to scornful and that featured unprompted metaphors to get their points across.

Comparing prostate cancer screening to Goldilocks, who finally arrives at the "just right" bowl of porridge after trying other problematic bowls, is off the mark at this time, suggested Ruth Etzioni, PhD, a biostatistician at Fred Hutchison Cancer Research Center in Seattle, Washington.

The contention that prostate cancer screening can be substantially improved (ie, "just right") depends on the idea that it can be personalized, which is "completely hyped," Etzioni told Medscape Medical News. "There is way too much excitement about an idea that at this point seems very elusive," she  said.

"It's the idea of the right shoe for every foot — like Cinderella," she added.

Early detection of prostate cancer is a "massive endeavor and so many things can go wrong when you are testing a large population," said Etzioni.

However, she agreed with the position statement authors that, with the increasing use of active surveillance, harms caused by treatment have been reduced.

Like the position statement authors, Etzioni believes that PSA may have considerable value as a single midlife test, which has been found to predict risk for later fatal prostate cancer, as previously reported by Medscape Medical News.  She says the risk-stratification approach needs further validation.

On the other hand, another expert, who is an outspoken critic of PSA testing, had boxing words for the position statement.

"This is a pathetic commentary meant to salvage a costly, unproven, and harmful intervention that is on the ropes of medical opinion," said Vinay Prasad, MD, from the Knight Cancer Center, Oregon Health and Sciences University in Portland, in an email to Medscape Medical News.

"We have subjected massive numbers of men with disease that was destined to do nothing (the overdiagnosed patients) to treatments that worsened sexual, urinary, or rectal function," said Prasad.

"There remains no credible evidence that some novel screening strategy saves lives or improves quality of life. The authors want us to think this evidence has magically appeared, but it hasn't. The USPSTF now gives PSA screening a Grade C recommendation. But make no mistake, that isn't good," he contended, referring to the US Preventive Services Task Force's 2017 upgrade from an earlier Grade D, after tremendous outcry from the urology community and other groups.

The position statement authors point to the management of an elevated PSA at screening as a sign of progress. Lead author, Faiena, explained that now "there are a number of blood-based ancillary tests, as well as imaging modalities, such as MRI, that can help guide the decision to biopsy." He said tests such as PCA3, PHI, and 4K score "are useful in helping to stratify patients."

Faiena acknowledged that shared decision-making "has not been evaluated in terms of prostate-specific outcomes" and that "the main benefit lays in patient confidence in the treatment plan proposed."

Primary Care Docs Can't Do This

In the second essay, a trio of US physicians call shared decision-making a "mirage" because of the many obstacles that prevent its actualization in primary care settings and the evidence that physicians still unilaterally order most PSA tests.

The obstacle list includes time pressures, competing clinical demands, low health literacy, shifting expert viewpoints, fear of litigation, and language and cultural obstacles, say oncologists Paul Mathew, MD, and Hilal Hachem, MD, from the Tufts Medical Center, Boston, Massachusetts, and internist Paul Han, MD, MPH, from the Maine Medical Center in Portland.

Their essay was published February 22 in JAMA Oncology.

The authors say a shared decision is a mirage because it does not play out in reality. Academics who write position statements and guidelines don't fully recognize the "practical infeasibility" of shared decision making, they claim.

National surveys of patients show that as many as two thirds of men who have a PSA test cannot recall a conversation about it, the authors also point out.

Doctors also struggle with the complexities of PSA screening. "Many physicians find it difficult to understand and communicate why the harms and benefits associated with PSA testing are close to being equal," say the essay authors.

The essayists also point out that no payment is involved. "Because there are no incentives for shared decision making, either through quality metrics or reimbursement for time spent, it is difficult to envision a nationwide shift in this fundamental reality of primary care," they write.

More troubling than a mirage, "quicksand" lies ahead should a PSA test occur and be elevated, say the authors That's an apt comparison, they believe, because a "cascade of events can follow that, once set in motion, can be difficult or impossible to slow down or reverse."

The cascade may include antibiotics, false-positive result, secondary assessments that use blood and urine biomarkers, and MRI. In the event of prostate cancer, additional molecular testing may be ordered, along with MRI if not done previously.

Furthermore, should definitive treatment occur, there is a "high" rate of complications.

The math is discouraging, the authors say: "The mortality benefit of 1 life saved per 1000 patients screened for prostate cancer over a 13-year period is set against the earlier physical, emotional, and financial impact of risks and complications."

The authors summarize with one last metaphor: "Once elevated PSA level is detected, without evidence-based consensus guidelines to shape common practice, physicians and their patients may find themselves in a quicksand of multiple expensive tests of uncertain value. The hope that physicians and patients can together stumble into an oasis where benefit abides and harm is dissipated therefore remains tenuous."

The statement authors include multiple authors with ties to pharmaceutical companies with prostate cancer–related drugs and one author with ties to multiple makers of prostate cancer markers. The essay authors have disclosed no relevant financial relationships. Prasad and Etzioni have disclosed no relevant financial relationships.

J Clin Oncol. Published online February 5, 2018. Abstract

JAMA Oncol.  Published online February 22, 2018. Abstract

Follow Medscape senior journalist Nick Mulcahy on Twitter: @MulcahyNick

For more from Medscape Oncology, follow us on Twitter: @MedscapeOnc


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