According to recent results published in the International Journal of Cancer, a urine test that can detect a genetic mutation (error) referred to as microsatellite instability (MSI) appears to accurately detect the recurrence of bladder cancer.
Bladder cancer is a common cancer, with approximately 55,000 new cases diagnosed in the United States each year. Superficial bladder cancer refers to cancer that has not spread to muscles of the bladder or nearby lymph nodes. Recurrence of superficial bladder cancer is common, often with the cancer invading the muscle of the bladder and necessitating surgery to remove the cancer. Patients who have undergone initial treatment for superficial bladder cancer often receive follow-up cystoscopies in order to detect a recurrence. A cystoscopy is a procedure that involves the placement of a lighted tube into the bladder so the physician can detect any abnormal areas of tissue indicative of cancer. Due to the invasiveness and discomfort of this procedure, researchers are evaluating novel approaches to detect recurrent cancer.
Researchers form France recently conducted a clinical study to determine the accuracy of detecting recurrent bladder cancer through a urine test that detects MSI. Previous studies have indicated that MSI appeared effective at initially detecting bladder cancer, but clinical studies evaluating the effectiveness of MSI in detecting recurrent bladder cancer had not been conducted. This study included 47 patients who had already been diagnosed with superficial bladder cancer and received treatment. Urine samples to test for MSI were done prior to the patients’ initial and follow-up cystoscopies for 12 to 48 months. MSI testing accurately identified 12 of the 13 cancer recurrences. Furthermore, MSI testing detected the cancer recurrences several months before detection was possible with cystoscopy.
These researchers concluded that MSI testing through a urine test appears to accurately detect cancer recurrences in patients treated for superficial bladder cancer. Future clinical trials will undoubtedly further reveal the clinical role of MSI testing either for initial screening and/or testing for bladder cancer or for the detection of cancer recurrences. Patients treated for superficial bladder cancer may wish to speak with their physician about the risks and benefits of participating in a clinical trial further evaluating MSI or other novel screening approaches. Sources of information regarding ongoing clinical trials include the National Cancer Institute (cancer.gov).
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Reference: Amira N, Mourah S, Rozet F, et al. Non-invasive molecular detection of bladder cancer recurrence.
International Journal of Cancer. 2002;101:293-297.