Stanford Scientists Develop Cell-Free RNA Urine Test for Bladder Cancer Detection
Scientists at Stanford University have developed a cell-free RNA urine sequencing test that identifies bladder cancer and detects residual cancer cells after treatment. The method captures short RNA fragments from urine samples to analyze thousands of gene signals, offering a less invasive tracking alternative to repeated cystoscopy examinations.
Urine RNA Sequencing Identifies Tumor Molecular Clues
Cell-free RNA floats outside intact cells within bodily fluids like blood, saliva, and urine. While cancer cells release these RNA strands, urine typically contains low volumes of fragmented RNA that complicate analysis. The Stanford research team isolated these short sequences and used genetic sequencing to map gene activity. Healthy subjects showed cell-free RNA originating primarily from genitourinary organs such as the bladder, kidneys, and prostate. By contrast, samples from bladder cancer patients displayed gene expression profiles closely matching tumor tissue.
Urine RNA Model Outperforms Traditional Bladder Cancer Tests
The urine cell-free RNA detection model achieved a sensitivity rate of approximately 95 percent during validation trials, correctly identifying 95 out of 100 localized bladder cancer patients. The false-positive rate for individuals without cancer remained at roughly 10 percent. The test performance exceeded traditional urine cytology methods and some urine-based tumor DNA assays. Researchers tracked 36 treated bladder cancer patients, observing that pre-surgery urine samples consistently contained bladder cancer RNA. Post-treatment RNA signals faded in patients without recurrence, while individuals who later experienced high-grade recurrence largely retained detectable cancer-related RNA.
Prediction Model Helps Clinicians Adjust Treatment Strategies
The research team built a treatment response prediction model using data from 114 patients. The model separated successful treatment outcomes from poor responses, and those predictions correlated with future recurrence risk. The findings suggest that future clinicians might adjust treatment strategies by evaluating cell-free RNA results alongside tumor size and pathological grading. The study findings were published in the medical journal Nature Medicine.