Five-yearly blood test could revolutionize prostate cancer screening

A simple blood test every five years is sufficient to screen low-risk men for prostate cancer, a new study shows.

PSA blood test checks prostate specific levels antigen, a marker for prostate cancer. Lithuania is the only country in Europe that routinely tests men for prostate cancer based on PSA levels, as the test was historically considered unreliable.

German research presented today at the European Association of Urology (EAU) General Assembly in Paris [April 6, 2024]more than 12,500 men aged 45 to 50 years have participated in the ongoing PROBASE trial, which tests different prostate cancer screening protocols.

This research has also been accepted for publication in the following journals: european urology.

PROBASE will recruit 45-year-old men and divide them into three groups based on their initial PSA test. A man whose PSA level is less than his 1.5 nanograms per milliliter (ng/ml) is considered low risk and will be followed up with his second test in five years. Men with a PSA level of 1.5 to 3 ng/ml are considered intermediate risk and will be followed for two years. People with PSA levels above 3 ng/ml are considered high risk and undergo an MRI scan and biopsy.

Of the more than 20,000 men recruited to the trial and judged to be low risk, 12,517 have now undergone a second PSA test at age 50. The researchers found that only 1.2% of them (146 people in total) had high levels of PSA (above 3ng/ml). ) was referred for MRI and biopsy. Only 16 of these men were subsequently found to have cancer, making him just 0.13% of the entire cohort.

The EAU requires that men be offered a risk-adapted strategy (based on initial PSA level), with a 2-year follow-up interval for those initially at risk, including those with a PSA level below 1 ng/ml. It is recommended that men who are older than their age be included. New findings suggest that screening intervals for people at low risk could be made much longer while minimizing additional risk.

By raising the low-risk threshold from 1 ng/ml to 1.5, 20% more men in the cohort were able to wait longer between tests, and fewer people developed cancer during that time. With nearly 14 million men in Europe between the ages of 45 and 50, the number of people affected by these changes would be significant. Although our research is still ongoing, it may turn out that even longer screening intervals, 7, 8, or even 10 years, are possible without additional risk. ”

Peter Albers, Principal Researcher, Department of Urology, Heinrich Heine University, Professor Düselldorf

Prostate cancer screening has historically been controversial, with concerns raised about both false positives leading to unnecessary invasive treatments and false negatives leading to missed cancers. This situation is gradually changing with the use of MRI scans, which can avoid unnecessary biopsies, and 'active surveillance', where men with early-stage cancer are monitored and treated only if the disease progresses. there is.

Prostate cancer screening guidelines are contradictory and unclear

Further research presented at the EAU conference shows that current guidelines and policies by European governments and health institutions remain contradictory and unclear, leading to high levels of opportunistic testing and unequal access to early diagnosis. ing. This study reviewed early detection policies across the European Union and conducted focus groups with urologists to identify how guidelines are interpreted in clinical practice.

The study was conducted by Dr. Katharina Bayer from the Department of Urology at the Erasmus MC Cancer Institute in Rotterdam, the Netherlands. She said: “Some countries have guidelines that are actively against testing, others are non-mandatory, and some countries, like Lithuania, have some form of testing. But in many countries “If you request a test, you can get a test, and in some cases it's free.” This means that highly educated men who know about the PSA test are more likely to be screened and receive an early diagnosis, while men with less knowledge are at a disadvantage. ”

This is a similar situation in the UK, according to Professor Philip Cornford of Liverpool University Hospitals NHS Trust, who chairs the EAU Prostate Cancer Guidelines Committee.

Professor Cornford said: “The NICE guidelines here in the UK are contradictory. They say there is no evidence that a PSA test is of any value, but at the same time anyone can have a PSA test if they wish. “The results are sufficient,” he said. – Educated and motivated men ask, but others, including many African-Caribbean men who are actually at higher risk, don't, so prostate cancer goes unnoticed.

“There is clearly a need for more organized prostate cancer testing and in November last year the UK government and charity Prostate UK announced a £42 million research plan to investigate this. should be published soon. Countries will now need to design screening programs that suit their national health systems and available resources. There's still a lot more to come, and new discoveries like the PROBASE trial can help us design appropriate screening programs, both in the UK and the rest of the world. ”