A multivariable model that includes mpMRI and blood testing assessment of prostate extracellular vesicles had a significantly higher AUC and sensitivity rate than mpMRI alone for predicting clinically significant prostate cancer, according to research presented at the American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO-GU).
Combining multiparametric magnetic resonance imaging (mpMRI) with prostate extracellular vesicle assessment and prostate-specific antigen (PSA) density may facilitate improved prediction of clinically significant prostate cancer (csPCa) and help reduce unnecessary prostate biopsies.
For the study, recently presented at the American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium (ASCO-GU) in San Francisco, 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 prostate-specific antigen (PSA) level of 6.4 ng/mL, according to the study.
For the detection of csPCa, 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 percent area under the curve (AUC) for predicting csPCA in comparison to 77 percent for the mpMRI/STEAP1-EV density combination model and 66 percent for mpMRI alone.
While the mpMRI only model demonstrated the highest sensitivity rate at 95.2 percent (in comparison to approximately 90 percent for the aforementioned combination models), the study authors noted the multivariable model had a 68.7 percent specificity rate that was 22 percent and 31 percent higher than the mpMRI/STEAP1-EV density combination model (46.7 percent) and the mpMRI alone models (37.6 percent) respectively.
“The combination of mpMRI with (prostate EV) and PSA derivatives demonstrated better predictive ability for csPCa on biopsy compared to imaging or serum testing alone,” wrote lead study author Cameron J. Britton, M.D., a urologist affiliated with the Mayo Clinic in Rochester, Minn., 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.
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. Poster presented at the 2024 American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium (ASCO-GU, San Francisco, Calif. Poster available at https://conferences.asco.org/gu/abstracts . Accessed January 29, 2024.