Prostate cancer screening performs as well as breast cancer screening - so why don't we do it?

Breast cancer screening has been standard across Europe for three decades. Organized programs send invitations, women show up for mammograms, and the system catches cancers early enough to save lives. Prostate cancer screening, despite involving the most commonly diagnosed cancer in European men, has no equivalent organized program. The contrast is stark, and a new analysis from the German Cancer Research Centre argues it may no longer be defensible.

The same disease burden, different policy responses

Breast and prostate cancer are the most commonly diagnosed cancers among European women and men, respectively. Both are treatable when caught early. Both screening approaches have documented mortality benefits. But while mammography programs have been running for decades, prostate cancer screening has been held back by concerns about the PSA blood test - specifically, worries about false positives leading to unnecessary biopsies and overdiagnosis of slow-growing cancers that would never have caused harm.

Those concerns were legitimate when the data was thin. But several European prostate screening trials have now reported long-term outcomes showing reduced mortality risk - reductions similar to those achieved by breast screening.

The new analysis, presented at the European Association of Urology Congress (EAU26) in London and accepted for publication in European Urology, puts the numbers side by side for the first time.

39,000 men versus 2.8 million women

Researchers led by Sigrid Carlsson at the German Cancer Research Centre (DKFZ) in Heidelberg compared data from 39,392 men who received initial PSA testing in the PROBASE prostate cancer screening trial (at ages 45 or 50) with data from over 2.8 million women aged 50-69 who underwent mammography in Germany's established breast cancer screening program.

The comparison found several notable patterns. PSA testing followed by MRI produced more false positives than mammography - 37-42% versus 10%. But here's where the picture shifts: after risk stratification (using additional factors to determine the likelihood of significant cancer), similar proportions of men and women were actually referred for biopsy - 0.8-2.4% for men compared with 1.1% for women.

And when biopsies were performed, prostate screening was far more efficient. Between 50% and 68% of prostate biopsies identified significant cancer, compared with just 10% of breast biopsies. That means fewer men were subjected to unnecessary invasive procedures relative to the total biopsy count.

The rates of invasive cancers detected were comparable: 60-74% for prostate screening versus 73% for breast screening. Prostate screening did identify somewhat more non-aggressive cancers (26-31% versus 22%), but the researchers note that active surveillance - monitoring low-grade prostate cancers and treating only if they progress - is well established and would limit the risk of overtreatment.

Comparing apples and slightly different apples

The researchers themselves urge caution. This analysis compares a clinical trial (PROBASE) with a population-based screening program - two different study designs that don't allow exact like-for-like comparison. The populations differ in age ranges and demographics. And comparing across two different cancers inherently limits how far conclusions can be pushed.

Carlsson acknowledged these constraints but argued that the data supports informed assumptions about what would happen if prostate screening were extended to the wider population. The outcomes, she said, are likely to be very similar to breast cancer screening.

Tobias Nordstrom, a clinical urologist and associate professor at the Karolinska Institute in Sweden, agreed that the comparison is challenging but called the overall similarities encouraging. Prostate cancer screening, he said, is clearly moving in the right direction toward ensuring it offers more benefits than harm.

The cost question

The clinical case for organized prostate screening is strengthening, but a key unanswered question is economic. Carlsson noted that the final piece is understanding what population-based prostate screening would cost compared with what is already being spent on the current patchwork of opportunistic screening - where men self-refer for PSA tests based on individual decisions rather than systematic invitation.

That economic analysis is already underway. If the numbers favor organized screening - or at least show it's no more expensive than the current ad hoc approach while delivering better, more equitable outcomes - the policy argument becomes hard to resist.

For now, the message from this analysis is that the clinical performance gap between prostate and breast cancer screening is smaller than many policymakers assume. Whether that translates into organized programs across Europe is a political and economic decision as much as a scientific one.