Undergoing a prostate-specific antigen (PSA) blood test every 5 years may be adequate for screening low-risk men for prostate cancer, according to recent findings presented by Albers et al at the European Association of Urology (EAU) Congress 2024 and simultaneously published in European Urology.
Background
Prostate cancer screening has historically been a controversial subject, involving concerns centered around false-positive results leading to unnecessary invasive treatments and false-negative results leading to missed cancer diagnoses. However, magnetic resonance imaging (MRI) scans and active surveillance has recently helped patients, especially those with early-stage disease, avoid unnecessary biopsies and undergo treatment only if their disease progresses.
Among European countries, PSA blood tests are only used routinely in Lithuania to screen men for prostate cancer, because the tests have historically been seen insufficiently reliable.
The EAU currently recommends men should be offered a risk-adapted strategy based on their initial PSA levels, with follow-up intervals of 2 years for those initially at risk, including those with levels higher than 1 ng/mL.
Study Methods and Results
In the recent study, researchers recruited 12,517 male patients (aged 45–50) participating in the ongoing PROBASE trial—which is currently examining different prostate cancer screening protocols. Patients were categorized into three groups based on their initial test results: those with PSA levels < 1.5 ng/mL (low risk), those with levels between 1.5 and 3 ng/mL (intermediate risk), and those with levels > 3 ng/mL (high risk). Low- and intermediate-risk patients are subsequently followed with second PSA tests after a respective 5 and 2 years, whereas high-risk patients receive an MRI scan and biopsy.
Among more than 20,000 low-risk patients enrolled in the trial, 12,517 have received their second PSA tests at the age of 50. The researchers found that 1.2% (n = 146) of these patients had PSA levels > 3 ng/mL and were referred for an MRI and biopsy. A total of 11% (n = 16) of the patients with these higher levels—comprising 0.13% of the total cohort—were found to have prostate cancer.
The researchers further reviewed early-detection policies across the European Union and carried out focus groups with urologists to identify how guidelines were interpreted in clinical practice. They revealed that current guidelines and policies from European governments and health-care institutions remain contradictory and unclear, resulting in high levels of opportunistic testing and disparities in access to early diagnosis.
“Some country’s guidelines are actively against screening, others are noncommittal, and a few—such as Lithuania—have some form of screening. [Nonetheless], in many countries, if [patients] ask for a test, [they] can get one, sometimes free and sometimes not. This means well-educated men who know about PSA tests are more likely to be screened and get an early diagnosis, while others with less knowledge are at a disadvantage,” emphasized co–study author Katharina Beyer, PhD, of the Department of Urology at the Erasmus MC Cancer Institute, the Netherlands.
“The NICE guidelines … in the UK are incongruous. They say there’s no evidence that PSA screening is worthwhile, but at the same time say any man can ask for a … test if [he wants] it. The result is that well-educated, driven men ask, and others, including many Afro-Caribbean men who are actually at higher risk, don’t ask, and so prostate cancers get missed,” added Phillip Cornford, BSc, MBBS, FRCS, MD, FEBU, Professor at Liverpool University Hospitals National Health Service Trust and Chair of the Prostate Cancer Guidelines Committee at the EAU.
Conclusions
The recent findings indicate the screening interval for low-risk patients may be much longer with minimal additional risk.
“By raising the bar for low risk from 1 ng/mL to 1.5, we enabled 20% more men within our cohort to have a longer gap between tests, and very few contracted cancer in that time. With nearly 14 million men aged between 45 [and] 50 in Europe, the numbers affected by such a change would be significant. Our study is still underway, and we may find that an even longer screening interval, of 7, 8, or even 10 years, is possible without additional risk,” underscored lead study author Peter Albers, MD, of the Department of Urology at Heinrich-Heine University Düsseldorf.
“There is clearly a need for more organized prostate cancer screening. [In] November [2023], the UK government and the charity Prostate UK announced a £42m research program to look at this. The details should soon be made public. Each country will need to design a screening program that fits their health system and the resources they have available, [b]ut there is still plenty we can learn from other countries and the work underway in the [European Union]. New findings, such as those from the PROBASE trial, can help us design an appropriate screening program both in the UK and elsewhere,” concluded Dr. Cornford.
