Christopher Filson, MD, on the evolving role of biomarkers in microhematuria workups

In this video interview, Christopher P. Filson, MD, MS, highlights the evolving role of urine-based biomarkers in the diagnostic workflow for patients who present with microhematuria. Filson is a urologic oncologist at Kaiser Permanente and a professor of clinical science at the Bernard J. Tyson Kaiser Permanente School of Medicine in Los Angeles, California.

A recent study on the real-world utility of a urine-based biomarker test, CxBladder Triage, showed that patients who were found to have a low probability of cancer were less likely to undergo cystoscopy.¹ Filson emphasized the importance of interpreting these findings in the context of the updated American Urological Association guidelines, which now recommend a more risk-stratified approach to hematuria workups. According to Filson, biomarkers are best positioned for patients with intermediate-risk microscopic hematuria, rather than those with gross hematuria or significant risk factors such as heavy tobacco use, who should continue to receive a full diagnostic evaluation. Conversely, low-risk patients no longer require biomarkers, as guideline recommendations support repeat urinalysis alone in this group.

Filson also highlights ongoing challenges and opportunities for improvement. While patients identified as having a low probability of cancer were less likely to undergo cystoscopy, overall cancer detection rates remain relatively low, even among those classified as high probability by biomarkers. This suggests a need to further refine and enhance biomarker specificity.

Additionally, he notes that approximately 20% of patients deemed high risk did not ultimately undergo cystoscopy, raising important questions about patient- and physician-level barriers to follow-up. Filson concludes that future efforts should focus not only on improving biomarker performance, but also on optimizing their implementation, adoption, and integration into shared decision-making around invasive diagnostic procedures.

REFERENCE

1. Filson CP, Slezak JM, Luong TQ, Aboushwareb T, Loo RK. Real-World Utility of Cxbladder Triage for Patients with Microhematuria: A Matched Cohort Study. Urol Pract. 2026:101097UPJ0000000000000972. doi:10.1097/UPJ.0000000000000972