A new blood test for prostate cancer has been shown to avoid more than half of unnecessary biopsies. The study, announced in San Francisco, states that the new test does not sacrifice accuracy.
Had the new test, called the Stockholm3 biomarker, been used on the men in the study, 56% would have been spared the discomfort of undergoing a biopsy.
Sensitivity, specificity, and predictive values with the new test either approximated or surpassed those achieved with conventional PSA testing, reported Scott Eggener, MD, of the University of Chicago.
“Stockholm3 has the potential to reduce unnecessary harms of prostate cancer screening,” said Eggener. “Stockholm3 has attractive characteristics and [demonstrated] successful recruitment of a large number of men from traditionally underrepresented minorities. The Stockholm3 should be available in the early part of 2024.”
In response to a question, Eggener noted that the 16% rate of MRI use in the study was lower than might be expected in a population-based investigation, probably because more than half of the blood specimens were archival from a biobank.
“It would be interesting to see if prospective routine use of MRI would change the operating characteristics,” he said.
A final question related to investigators’ ability to recruit a racially/ethnically diverse population, as Asian, Black, and Hispanic patients accounted for a majority of the blood specimens. Eggener said investigators sought out participating sites that have diverse patient populations.
Eligible participants were ages 45-75, had no known prostate cancer but a clinical indication for prostate biopsy, and self-identified as Asian, Black/African American, Hispanic/Latino nonwhite, or white. All participants had blood drawn prior to prostate biopsy.
Key Findings
Investigators achieved the ethnic diversity they sought, as 16% of patients were Asian, 24% were Black, 14% were Hispanic, and 46% were white. Biopsy results showed benign disease in 57% of cases, GG 1 prostate cancer in 14%, and GG ≥2 in 29%. Analysis of biopsy findings by ethnicity showed that Asian and Hispanic men had more benign disease (69% and 60%, respectively) and Black men had fewer benign diagnoses (49%).
Disclosures
The study was sponsored by the Karolinska Institute.
Eggener disclosed relationships with A3P Biomedical (Stockholm3 developer), Candel Therapeutics, Cellvax, Janssen, MetasTx, and OptumHealth.Source: Genitourinary Cancers Symposium. Vigneswaran HT, et al “SEPTA: Stockholm3 validation study in a multi-ethnic cohort for prostate cancer detection” GuCS 2024; Abstract 262.