Scientists believe they've found a simple new test to detect kidney cancer in its earliest and most curable stage.
In a report published in this week's Cancer Research, researchers outline a method based on an analysis of a person's urine.
Kidney cancer accounts for about 3 percent of all cancers. About 32,000 cases were identified in the United States in 2003. Doctors currently use several methods to diagnose the disease, including magnetic resonance imaging, computed tomography scans, ultrasounds, and, ultimately, biopsy. Since diagnosis is difficult, about 25 percent to 40 percent of people who are diagnosed with the disease are already in an advanced stage. However, the cancer is often curable if caught early. Finding a simple and accurate method to identify early kidney cancer is considered paramount to improving prognosis for these patients.
Researchers from Fox Chase Cancer Center in Philadelphia used a molecular DNA-based test to look for genetic alterations in the urine known to play a role in the development of kidney cancer. Fifty patients with the disease were tested, and 44 were found to have genetic alterations in their urine identical to the genetic alternations found in their tumors upon biopsy. Even more encouraging was the test's ability to identify those with early stage disease. A control group of people without kidney cancer also received the test. None of their urine samples were positive for the genetic alterations.
"The test is remarkably accurate with no false-positives in this study," says co-author Robert G. Uzzo, M.D., from Fox Chase Cancer Center. He says: "In addition, one of the most impressive outcomes of this research is that the test also identified 27 of the 30 patients with stage 1 disease. Finding these cancers early means earlier treatment and better prognosis."