A multi-center trial published in the Journal of Clinical Oncology reveals that the Stockholm3 blood test may significantly reduce the number of unnecessary prostate biopsies while maintaining comparable sensitivity to the standard prostate-specific antigen (PSA) test across various racial and ethnic groups. The study, led by Adam B. Murphy, MD, MBA, from Northwestern University, enrolled over 2,100 patients from 17 clinical sites across the U.S.
Study Design and Patient Demographics
The study population included a diverse group of participants: 16% Asian, 24% Black or African American, 14% Hispanic white, and 46% non-Hispanic white. Researchers collected patient samples to measure the Stockholm3 risk score, which incorporates protein biomarkers, genetic biomarkers, and clinical information to assess individual prostate cancer risk, prior to biopsy.
Key Findings
The results indicated that the Stockholm3 test reduced biopsies for benign and low-grade prostate cancer by 45% overall. This reduction was consistent across different racial and ethnic subgroups, ranging from 42% to 52%. Notably, the test demonstrated similar sensitivity to the PSA test but with nearly three times higher specificity. The team also found that the threshold in Black men was lower to achieve greater than 90 percent detection.
Expert Commentary
Dr. Murphy emphasized the importance of these findings, stating, "The study recruited patients from 17 sites to achieve racial and ethnic diversity to permit a thorough subgroup analysis of accuracy, which is a remarkable thing and that’s how validations should be done." He further added, "This study is a model for what should be done when tests are being applied across the general U.S. population, especially in this era of precision medicine and precision oncology."
Implications for Prostate Cancer Screening
Prostate cancer is a significant health concern, being the second-leading cause of cancer death in men in the U.S. Current screening methods involve a digital rectal exam and PSA testing, often followed by a prostate biopsy. The Stockholm3 test offers a potential improvement by reducing the number of unnecessary biopsies, particularly benefiting men at higher risk, including older men, those with a family history of prostate cancer, and African American men, who have a disproportionately higher risk.
Funding and Support
This research was supported by the Vetenskapsrådet (Swedish Research Council), Cancerfonden (Swedish Cancer Society), and A3P Biomedical.
