A novel prostate cancer test, known as Stockholm3, demonstrates a superior ability to detect dangerous tumors compared to the conventional prostate-specific antigen (PSA) screening method, according to a recent study.
Researchers from the Karolinska Institute in Stockholm developed the Stockholm3 test, which integrates PSA measurements with genetic markers associated with heightened prostate cancer risk. It also incorporates additional relevant blood proteins, age, family history, and prior biopsy results to generate a risk score. This score estimates an individual's likelihood of having clinically significant prostate cancer, defined in the study as disease above grade two.
The study, which involved 12,670 men aged 50 to 74, found that Stockholm3 identified 90 percent of clinically significant prostate cancers. This contrasts with the standard PSA test, which identified 74 percent. Over a two-year follow-up period, the new test missed only 10 percent of these significant cancers, compared to 26 percent missed by PSA screening. The rate of false positives was comparable between both tests.
Prostate cancer is the most common cancer among men in the UK, with approximately one in eight men affected annually. The PSA test, the current primary screening tool, measures a protein produced by the prostate gland. However, elevated PSA levels can be caused by conditions other than cancer, leading to potential false positives and unnecessary biopsies, or false negatives that miss aggressive tumors.
Authors of the study noted that in their screening cohort with short-term follow-up, Stockholm3 offered a greater clinical benefit by detecting more clinically significant prostate cancers due to fewer false-negative results. They suggest that integrating Stockholm3 into screening pathways could enhance the efficiency and clinical utility of prostate cancer screening programs, provided further long-term studies confirm its effectiveness and cost-efficiency.
This development follows recent discussions about alternative prostate cancer screening approaches. One proposed method involves using MRI scans after a positive PSA test before considering a biopsy. Experts suggest this could allow for earlier detection and action on lower PSA levels. Recommendations have also been made for a more personalized screening approach based on individual risk factors, rather than a universal age-based program. Under such a model, men at lower risk might undergo MRIs every four to five years, while those at higher risk, including Black men and individuals with a genetic predisposition, would be screened more frequently. Biopsies would be reserved for cases with clearly suspicious results on MRI scans.
In parallel, UK health officials have made a commitment to expand a trial for diagnostic tests and scans. This trial will now invite all Black men aged 45 to 74, who have not had a PSA test or MRI prostate scan in the past five years, to participate. This initiative aligns with campaigns advocating for a national screening program, initially focused on high-risk groups such as Black men and those with a family history or specific genetic mutations.