TUESDAY, June 14, 2011 (HealthDay News) -- A genetic test to help doctors evaluate whether women with breast cancer are candidates for treatment with the drug Herceptin (trastuzumab) has been approved by the U.S. Food and Drug Administration.
The Inform Dual ISH test measures whether there are excessive copies of the HER2 gene in breast tumor tissue. HER2-positive breast cancer is a fast-growing, aggressive form of the disease, making up about 20 percent of all breast cancer cases, the FDA said in a news release. Women with an above-normal number of copies of the HER2 gene are candidates for Herceptin therapy.
Clinical studies involving 510 women with breast cancer showed the new test was 96 percent accurate in identifying HER2-positive tumor samples, the agency said. The test correctly identified HER2-negative tumors in 92.3 percent of cases.
Breast cancer is the second-leading cause of cancer deaths among women, the FDA said, citing some 207,090 cases diagnosed in the United States last year, and about 39,840 deaths from the disease.
The new test is produced by Ventana Medical Systems, based in Tucson, Ariz.
The U.S. National Institutes of Health has more about breast cancer.