Urine Liquid Biopsy Shows Strong Promise for Guiding Bladder Cancer Treatment — Clinical Trials on the Horizon
Key Insights
A Stanford-developed urine tumor DNA (search) test filters out age-related background mutations to predict bladder cancer (search) recurrence with high accuracy, identifying three distinct molecular response classes among patients.
The test revealed roughly one-third of patients are cured by surgery alone, one-third respond to BCG immunotherapy (search), and one-third respond to neither, enabling precision-guided treatment decisions.
Stanford is converting the assay to CLIA-certified status and preparing prospective clinical trials for both treatment escalation and de-escalation strategies, with FDA approval described as "on the horizon."
A novel urine-based liquid biopsy developed at Stanford University is demonstrating remarkable accuracy in predicting bladder cancer (search) recurrence and may soon reshape how clinical trials enroll and treat patients. The test, developed by urologic oncologist Joseph Liao, M.D., and colleagues, filters out age-related background mutations in urine to produce a cleaner, more reliable signal for detecting residual cancer after surgery and immunotherapy.
Bladder cancer (search) is the fourth most common cancer in men and sixth most common overall, with roughly 70,000 Americans diagnosed with the non-muscle-invasive form each year. The current standard of care — endoscopic surgery followed by BCG immunotherapy (search) and lifelong cystoscopy surveillance — is burdensome, costly, and imprecise. BCG can cause significant discomfort and flu-like symptoms, faces recurring global supply shortages, and does not work for every patient. Yet under the current protocol, nearly all eligible patients receive it.
A Molecular Breakthrough in Risk Stratification
Liao's team set out to change that paradigm. Their urine tumor DNA (search) (utDNA) test, published recently in Cell, analyzed 261 patient samples and identified three distinct molecular response classes: those cured by surgery alone, those who respond to BCG following surgery, and those who respond to neither.
The key innovation is the removal of what the researchers call "clonal cystopoiesis" — benign, age-related somatic mutations that accumulate in bladder tissue and have previously caused false positives in other utDNA tests. By subtracting this background noise, the Stanford team's test produces a high-confidence signal: patients with detectable tumor DNA after completing BCG faced near-certain recurrence, while those who cleared the tumor DNA had excellent outcomes.
"If roughly a third of patients are cured by surgery alone, a third by surgery plus BCG, and a third by neither, precision-guided treatment could spare many patients from an ineffective and unpleasant therapy and preserve a scarce drug supply for those most likely to benefit," the researchers indicated.
From Discovery to Clinical Implementation
Now, the team is preparing to translate these findings into prospective clinical trials. The utDNA test is being converted into a CLIA-certified assay that can be processed by any appropriately certified laboratory, clearing the path for broader clinical use.
Once certification is complete, Stanford plans to launch both treatment escalation and de-escalation trials. In the escalation arm, patients who remain utDNA-positive after surgery and BCG — indicating minimal residual disease — would receive alternative or intensified treatment ahead of expected recurrence. The de-escalation arm would explore sparing surgery-only responders from BCG altogether.
FDA approval is described as "on the horizon," though Liao notes that a commercial industry partner would likely accelerate the path to market.
Expanding the Diagnostic Toolkit
Ongoing research is also exploring urine RNA analysis, AI-enhanced endoscopic imaging, and the test's applicability to monitoring responses to chemotherapy and other immunotherapies. These efforts reflect a broader movement toward noninvasive molecular diagnostics in urothelial cancer management.
The clinical implications are significant. By enabling precision-guided treatment decisions, the utDNA test could reduce unnecessary exposure to BCG's side effects, address supply shortage concerns, and direct more intensive therapy to patients who truly need it — all while providing a noninvasive surveillance option that may reduce reliance on repeated cystoscopy.