Study combines mpMRI with extracellular vesicle–based biomarkers for prostate cancer detection

Research sharing during the 2024 ASCO Genitourinary Cancers Symposium showed that a multipronged approach combining multiparametric magnetic resonance imaging (mpMRI) with extracellular vesicle–based and PSA-based biomarkers may enhance prediction of clinically significant prostate cancer and potentially reduce unnecessary prostate biopsies.¹

“Prostatic extracellular vesicles represent a promising biomarker with the potential for reduction of false positive rate in men with elevated PSA following mpMRI,” the authors wrote.

For the study, researchers reviewed data from 175 patients (median age of 65) who had mpMRI, blood tests and a prostate biopsy. The treatment cohort had a mean PSA level of 6.4 ng/mL, according to the study.

(Editor’s note: This article has been adapted from its original publication on our sister site Diagnostic Imaging.)

For the detection of clinically significant prostate cancer, researchers compared imaging alone with mpMRI, a model that combined mpMRI and six-transmembrane epithelial antigen of the prostate extracellular vesicle (STEAP1-EV) density and a multivariable model that combined mpMRI, STEAP1-EV density, PSA density and prostate health index (PHI) density.

Researchers found that the multivariable model had a 90% area under the curve (AUC) for predicting clinically significant prostate cancer in comparison to 77% for the mpMRI/STEAP1-EV density combination model and 66% for mpMRI alone.

While the mpMRI only model demonstrated the highest sensitivity rate at 95.2% (in comparison to approximately 90% for the aforementioned combination models), the study authors noted the multivariable model had a 68.7% specificity rate that was 22% and 31% higher than the mpMRI/STEAP1-EV density combination model (46.7%) and the mpMRI alone models (37.6%) respectively.

“The combination of mpMRI with (prostate EV) and PSA derivatives demonstrated better predictive ability for clinically significant prostate cancer on biopsy compared to imaging or serum testing alone,” wrote lead study author Cameron J. Britton, MD, a urologist affiliated with the Mayo Clinic, and colleagues.

Incorporating the assessment of blood concentrations of prostate extracellular vesicles into multivariable mpMRI models may help reduce unnecessary biopsies in high-risk patients, according to the study authors.

“Prostatic extracellular vesicles represent a promising biomarker with the potential for reduction of false positive rate in men with elevated PSA following mpMRI,” suggested Britton and colleagues.

Reference

1. Britton CJ, Andrews JR, Arafa A, et al. Prostate extracellular vesicles and prediction of clinically significant prostate cancer: a prospective single-institution pilot study. J Clin Oncol 42, 2024 (suppl 4; abstr 337). 10.1200/JCO.2024.42.4_suppl.337