When Jack Layton announced he has prostate cancer, most men I know could relate. They, too, have reached the age at which this diagnosis is not rare. Several of my friends and colleagues have been diagnosed with prostate cancer. They know survival rates are extremely high. But they all describe the treatment (and its aftermath) as deeply unpleasant, even traumatizing. They all dread the potential impact on their quality of life.
This year, more than 22,000 Canadian men will be diagnosed with prostate cancer. For health-conscious men, PSA tests are what mammograms are to women – an essential piece of preventive medicine. Men gripe because, unlike mammograms, their PSA tests aren't covered by health care. But a growing body of evidence shows that the PSA test is a very crude instrument, resulting in a huge number of unnecessary surgeries.
The trouble with the PSA test is that it can't reliably distinguish between the large number of prostate cancers that are “indolent” (slow growing and harmless) and the small number that are aggressive and deadly. And so we treat them all. Most men develop prostate cancer in late middle age, but it's rarely fatal. Only 3 per cent of them will die from it.
“The case for screening seems to be getting weaker and weaker,” says Laurence Klotz, chief of urology at Toronto's Sunnybrook Health Sciences Centre. For the record, he strongly believes in screening. But he's also among a growing number of experts convinced that prostate cancer is vastly over-diagnosed and over-treated. That's not just a problem for the system. Some of the men who get unnecessary surgery will go on to suffer impotence, incontinence and other miseries, both mental and physical. For them, the treatment is worse than the disease.
Recent large-scale studies, conducted on more than 250,000 men, have confirmed that – at best – PSA tests save few lives, at enormous cost. One widely cited study found that, for every man whose death was prevented by a PSA test, 48 men received needless treatment. Few men are aware of these statistics. How would you feel about prostate surgery if you knew the odds were roughly 98 per cent that you didn't need it?
Attitudes toward screening tests vary greatly across the Western world. In the United States, PSA screening is nearly universal. In England, it's rare. Canada, predictably, is somewhere in between. At Sunnybrook, Dr. Klotz has pioneered an “active surveillance” approach, which combines aggressive screening with much more conservative treatment for patients with low-risk cancers. He figures this approach could cut needless surgeries by half or more. His views are not so popular among doctors who think over-treatment is a small price to pay for saving lives. Some patients aren't that keen, either. “It often comes down to a judgment call,” he says. “When some patients hear a cancer diagnosis, the idea of not doing anything is completely unacceptable to them.”
The latest research findings are sobering news for a medical establishment that had invested high hopes in screening. The news is even more sobering for middle-aged men. Should you bother getting screened at all? And if your PSA levels are high, what then?
One day, we'll develop better screening techniques and lower-risk treatments. Until then, expert opinion is all over the map. “There is no imperative to be screened, or not screened, for prostate cancer,” writes Dartmouth's Gilbert Welch, an expert on cancer screening. “The only imperative is that men be informed about the consequences of either choice.” He argues that doctors (along with cancer agencies) haven't been very good at that. They've been so insistent about telling us to be vigilant about our health that they've neglected to mention the tradeoffs.
So far as I know, none of the men I know who've had prostate surgery ever contemplated any other option – even though the odds are good they never needed it at all.