From the Journals

Urine test shows promise for diagnosing urothelial carcinoma


 

FROM CLINICAL CANCER RESEARCH

A simple urine test can accurately diagnose urothelial carcinoma as well as predict the risk for recurrence for those under surveillance, according to findings from a recent validation study.

The urinary comprehensive genomic profiling (uCGP) assay (UroAmp, Convergent Genomics) had a specificity of 95% and sensitivity of 90% for an initial diagnosis of urothelial carcinoma in patients with hematuria – identifying 95 of 100 people with urothelial carcinoma and 90 of 100 patients without the disease.

For patients under surveillance for urothelial cancer recurrence, the test was six times more accurate than traditional clinical risk factors for predicting recurrence.

“Considering its performance in multiple areas of urothelial carcinoma diagnosis and monitoring, uCGP shows great promise to enhance delivery of risk-stratified care,” Keyan Salari, MD, PhD, director of the prostate cancer genetics program at Massachusetts General Hospital in Boston, and colleagues wrote in a study published in Clinical Cancer Research.

“The idea is that this could be used as kind of a first-pass screening tool for patients with hematuria that could potentially obviate the need for undergoing imaging such as CT scans or cystoscopy,” Dr. Salari said in an interview.

The uCGP test is a next-generation sequencing assay that identifies mutations in 60 genes associated with bladder cancer. An earlier analysis evaluating the test as a potential screening tool focused on 10 key genes covered in the assay. The study found the test accurately predicted future bladder cancer in 66% of urine samples, including some that had been collected more than a decade prior to being tested.

In the current case-control study, Dr. Salari and colleagues used a total of 581 samples – 333 samples for classifying disease and developing algorithms for initial diagnosis, surveillance, and molecular-grade prediction, as well as 248 samples for blinded validation. The test’s performance was evaluated by calculating sensitivity, specificity, positive predictive value, and negative predictive value.

Overall, the test demonstrated a specificity of 95% and sensitivity of 90% for an initial urothelial carcinoma diagnosis, but performed even better for the most aggressive tumors, with 100% sensitivity for diagnosing high-grade urothelial carcinoma and muscle-invasive tumors.

On the diagnosis front, the test had a positive predictive value of 88% and a negative predictive value of 99%.

Among patients under surveillance, the test predicted the risk of recurrence significantly better than standard clinical risk factors (hazard ratio, 6.2). The test demonstrated a positive predictive value similar to that observed for cytology (45% vs. 42%) but a much higher sensitivity (79% vs. 25%). The test also demonstrated a negative predictive value of 91% for recurrence.

The molecular-grade algorithm performed well, with a positive predictive value for high-grade disease of 88% and a specificity of 95% in the validation cohort.

Overall, “uCGP enables noninvasive, accurate urothelial carcinoma diagnosis and risk stratification in both hematuria and urothelial carcinoma surveillance patients,” the authors concluded. The test is not currently reimbursed by Medicare, but negotiations with third-party payers are reportedly underway.

The study was supported by the National Cancer Institute. Dr. Salari reported grants from Convergent Genomics during the conduct of the study as well as grants from Urology Care Foundation and Prostate Cancer Foundation, and personal fees from OrigiMed outside the submitted work. Several coauthors are employees and stockholders of Convergent Genomics.

A version of this article first appeared on Medscape.com.

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