CATEGORY: MEN’S HEALTH
A prostate cancer found by screening is not always a cancer worth finding. Many grow so slowly they would never have caused a symptom. Once one has a name, though, it often gets surgery or radiation, and those treatments leave some men incontinent or unable to have erections. A Swedish trial of 13,153 men aged 50 to 60 tried to shrink that problem. Screening there added an MRI scan, and men whose scan came back clear had no biopsy at all. That approach was followed by 57% fewer diagnoses of harmless prostate cancer, with no detectable loss in finding the dangerous kind.1
A Clear Scan Meant No Needle
Men came from the population register, invited for a PSA blood test. PSA is a protein the prostate makes, and a raised level can mean cancer or several harmless things. Anyone with a raised result got an MRI. Only then did the split happen, and it was a random draw rather than a doctor’s judgment. One path was the standard one: twelve tissue samples taken systematically, plus targeted samples of anything the scan had flagged. The other path skipped the biopsy entirely when the scan showed nothing suspicious. Men were re-invited for further rounds at two, four or eight years depending on their PSA level, so this covers repeated screening rather than a single test. A pathologist examined every sample and graded it. That grading is how the harmless was told from the dangerous.
185 Men Diagnosed Against 298
Prostate cancer of any kind turned up in 2.8% of the MRI-guided group and 4.5% of the group biopsied systematically. That is about 1.7 fewer men diagnosed per 100 screened. In counts, 185 against 298.1 Diagnoses of clinically insignificant cancer, the grade least likely ever to cause trouble, were 57% lower, with a range of 43% to 68%. Cutting those diagnoses was what the trial had been built to measure, while finding the dangerous kind was a secondary question.1 On that secondary question the two groups came out level. The first screening round produced about half as many harmless diagnoses under the MRI approach. Later rounds produced about a quarter as many. Serious complications were rare either way: five in all, across more than 13,000 men.
Diagnoses Were Counted, Deaths Were Not
Median follow-up was 3.9 years. That is long enough to count diagnoses and nowhere near long enough to count deaths, so nothing here says which approach saves more lives. The mortality analysis is years away. Cancers classed as advanced or high-risk were fewer in the MRI-guided group, 15 against 23, on numbers too small to rest a conclusion on. The men were Swedish, aged 50 to 60, and screened in a system with high-quality MRI and experienced radiologists. Scan quality is the assumption the whole approach rests on. Money came from Swedish cancer charities and public research bodies rather than from industry.
A Second Swedish Trial Found a Harder Trade
STHLM3-MRI, a separate screening trial, put a narrower question: what happens if the twelve standard samples are dropped in men whose scan has already flagged something. Detection of aggressive cancer fell by about 15%. For each harmless cancer avoided, roughly four aggressive ones went unfound.2 Which biopsies get skipped appears to decide how clean the trade is.
Key Takeaways
- An MRI-first approach in 13,153 Swedish men cut diagnoses of harmless prostate cancer by 57%, while the number of dangerous cancers found held level.
- Not being diagnosed is the gain here: harmless prostate cancers, once named, are often treated with surgery or radiation that carries lasting side effects.
- The trial ran 3.9 years and counted diagnoses. Whether either approach saves more lives remains unanswered.
References
- Hugosson J, Godtman RA, Wallström J, et al. Results after Four Years of Screening for Prostate Cancer with PSA and MRI. New England Journal of Medicine. 2024;391(12):1083–1095. link
- Chandra Engel J, Eklund M, Jäderling F, et al. Diagnostic effects of omitting systematic biopsies in prostate cancer screening. European Urology Oncology. 2025;8(2):435–443. link.