Bladder cancer lab test 4X more effective
effective than the conventional laboratory test in detecting the
disease, which is encouraging for sufferers of the fifth most
common cancer in the US.
Like all tumours, early detection of bladder cancer can make the difference in how successful chemotherapeutic treatment is. This new test and its dramatic improvement over existing procedures could potentially increase the success rates of treated patients and lower recurrence.
The NMP22 assay is believed to be the only point-of-care test approved by the Food and Drug Administration for the initial diagnosis and surveillance of bladder cancer.
It works by detecting elevated amounts of the NMP22 protein in just a few drops of urine. The test does not require cancer cells to be present in urine.
Test results can be read in the doctor's office in 30 to 50 minutes. With urine cytology, whole cells must be present in the urine, and the test must be performed in a laboratory.
Results typically are available in about a week after a sample has been collected.
The study, which appears in the Jan. 18 issue of the Journal of the American Medical Association, also discovered that in combining the NMP22 assay with cystoscopy significantly increased the overall detection rate to 99 per cent, compared with 91 per cent for cystoscopy alone.
Urine cytology combined with cystoscopy only increased detection to 94.2 per cent in this study.
"Many of our patients with bladder cancer live long after their disease is initially discovered and treated, but the rate of recurrence is very high," said Barton Grossman, professor in M. D. Anderson's Department of Urology and the study's principal investigator.
"Current recommendations indicate lifelong screenings, at least once a year, to monitor their status. A test like the NMP22 assay which is accurate and easy to administer, will help identify and treat patients earlier when they a have better chance for a good outcome," he added.
This study comes after an article last year in JAMA, also led by Grossman, found that the NMP22 assay was three times more effective than urine cytology for the initial diagnosis of bladder cancer for high-risk individuals.
For the 500,000 Americans with a history of bladder cancer, the probability of recurrence can be as high as 50 per cent depending on the stage, grade and number of primary tumours.
Risk factors for the disease include a history of smoking, exposure to certain industrial chemicals and being over age 40. Haematuria, or blood in the urine is a warning sign of bladder cancer.
A cystoscopy is currently considered to be the "gold standard" for bladder cancer detection. A cystoscopy is a low-risk procedure using a flexible endoscope to view the walls of the bladder. It is performed under local anaesthetic in a doctor's surgery.
"Until we reach 100 per cent for detection, there is always room for improvement," Grossman commented, "but I think many patients could benefit from a test like this that helps detect tumours before they become advanced and require more aggressive treatment."
