18-gene urine test may reduce unnecessary prostate biopsies

An 18-gene urine test demonstrated higher diagnostic accuracy for high-grade prostate cancer than existing biomarker tests, suggesting that the urinary panel may be used to avoid unnecessary biopsies in patients with elevated prostate-specific antigen (PSA) levels.¹

“In those men who have had a biopsy before and are being considered for another biopsy, MPS2 will identify half of those whose repeat biopsy would be negative," says John T. Wei, MD.

The test, called MyProstateScore2.0, or MPS2, builds on the original MPS test, which is currently endorsed by National Comprehensive Cancer Center guidelines for prebiopsy risk stratification and incorporates prostate cancer antigen 3, TMPRSS2:ERG gene fusion expression, and serum PSA level. The newly developed test is optimized to better detect high-grade or clinically significant prostate cancer, with models developed in parallel without prostate volume (MPS2) and with prostate volume (MPS2+).

“Our standard test is lacking in terms of its ability to clearly pick out those who have significant cancer. Twenty years ago, we were looking for any kind of cancer. Now we realize that slow-growing cancer doesn’t need to be treated. All of a sudden, the game changed. We went from having to find any cancer to finding only significant cancer,” explained co-senior author John T. Wei, MD, in a news release on the findings.² Wei is the David A. Bloom professor of urology at Michigan Medicine in Ann Arbor.

For the study, the MPS2 models were developed in a cohort of 761 men and validated in a cohort of 743 men. Of these, 293 men in the development cohort and 151 men in the validation cohort had high-grade prostate cancer detected on biopsy.

The area under the curve values for high-grade cancer with the MPS2 and MPS2+ models were 0.81 and 0.82, respectively, compared with 0.60 for PSA alone, 0.66 for Prostate Cancer Prevention Trial risk calculator, 0.77 for the Prostate Health Index, 0.76 for the derived multiplex 2-gene model, 0.72 for the derived multiplex 3-gene model, and 0.74 for the original MPS model.

The MPS2 models also demonstrated negative predictive values of 95% to 99% for cancers of grade group 2 or higher and of 99% for cancers of grade group 3 or higher across all pertinent subgroups.

Based on data from the study, the MPS2 models would have reduced 35% to 42% of unnecessary biopsies in the initial biopsy population, vs 15% to 30% reductions for other tests. In the repeat biopsy population, the MPS2 models would have led to reductions in unnecessary biopsies of about 46% to 51%, compared with reductions of 9% to 21% with other biomarker tests.

In total, the study included 761 men in the development cohort and 743 men in the validation cohort. The median age in the development cohort was 63 years, and the median PSA level was 5.6 (4.6-7.2) ng/mL. In the validation cohort, the median age was 62, and the median PSA level was 5.6 (4.1-8.0) ng/mL.

Wei concluded in the news release,² “In those men who have had a biopsy before and are being considered for another biopsy, MPS2 will identify half of those whose repeat biopsy would be negative. Those are practical applications for patients out there. Nobody wants to say sign me up for another biopsy. We are always looking for alternatives, and this is it.”

References

1. Tosoian JJ, Zhang Y, Xiao L, et al. Development and Validation of an 18-Gene Urine Test for High-Grade Prostate Cancer. JAMA Oncology. Published online April 18, 2024. doi:10.1001/jamaoncol.2024.0455

2. New urine-based test detects high-grade prostate cancer, helping men avoid unnecessary biopsies. News release. Michigan Medicine – University of Michigan. April 16, 2024. Accessed April 18, 2024. https://www.newswise.com/articles/new-urine-based-test-detects-high-grade-prostate-cancer-helping-men-avoid-unnecessary-biopsies