(Bruce Powell/AP Photo/University of Chicago Medical Center)

“There is a powerful narrative among support groups and cancer survivors: Screening saves lives. . .  For the most part, it’s wishful thinking. And it demonstrates the growing gap between what screening (and science more generally) can offer, and what the risk-averse public wants it to be.”—Globe and Mail, May 21, 2012

A recent recommendation by a U.S. government advisory panel to ditch the PSA test for prostate cancer has reignited the call for a cancer screening rethink. It’s no longer okay to abide by the “screen early, screen everybody” maxim, the conversation goes, echoing the one that emerged when the frequency of routine screening for breast cancer was scaled back last year.

Now, it’s good to be having these discussions: We do need to change how we think about cancer screening. In recent years, with the advent of incredible technologies that detect diseases before we feel sick, we’ve seen the emergence of “overdiagnosis.” The term describes cancer that is diagnosed but would not necessarily cause death or even symptoms because the cancer never grows, it regresses, or it spreads so slowly, the person dies before knowing any harm. That’s right, not all cancers are deadly or even harmful. As well, every single body displays at least a couple of benign abnormalities that can be seen as trouble. This is why mass screening has the potential to “rapidly turn perfectly healthy people into patients,” says the Canadian health policy researcher and author of Seeking Sickness, Alan Cassels.

Science-ish, though, wondered whether PSA testing and mammograms—usually the inspirations for the anti-screening cri de coeur because they can lead to overdiagnosis and unnecessary surgeries—are the exceptions in cancer screening or the rule.

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