FDA OKs Test to Spot HER2-Positive Breast Cancer
Inform Dual ISH test determines if breast cancer patients are candidates for trastuzumab
TUESDAY, June 14 (HealthDay News) -- The U.S. Food and Drug Administration has approved the Inform Dual ISH test, a genetic test to determine whether women with breast cancer are human epidermal growth factor receptor (HER)2-positive and therefore candidates for trastuzumab (Herceptin).
The Inform Dual ISH test, manufactured by Ventana Medical Systems, enables measurement of the number of copies of the HER2 gene, allowing lab personnel to count the number of copies of HER2 genes on chromosome 17 in a small sample of the breast tumor using a standard microscope. The test allows lab personnel to see and count copies of chromosome 17 and HER2 genes on the same slide without the need for a fluorescence microscope.
The approval of the genetic test was based on a study involving 510 patients with breast cancer. The data revealed that the test was effective in confirming that a patient's tumor sample contained more than the normal number of copies of the HER2 gene in 96 percent of the HER2-positive tumor samples. The data also revealed that the test was effective at excluding the possibility that more than the normal number of HER2 gene copies were present in 92.3 percent of the HER2-negative tumor samples. Patients with an excess number of copies of the HER2 gene are typically candidates for trastuzumab, while those who do not have more than the normal number of copies of the HER2 gene are typically not candidates for treatment.
"When used with other clinical information and laboratory tests, this test can provide health care professionals with additional insight on treatment decisions for patients with breast cancer," Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostic Device Evaluation and Safety in the FDA's Center for Devices and Radiological Health, said in a statement.