According to Dr. Lori J. Goldstein, director of Breast Evaluation Center at Fox Chase cancer Center in Philadelphia, the Oncotype DX test, which actually measures 21 different genes, was not designed to specifically test for HER2 and is not intended as a substitute for two other widely used and accepted lab tests.
The Inform Dual ISH test is manufactured by Ventana Medical Systems of Tucson, Arizona was recently approved by the FDA to test for HER2 gene. It has a 96% sensitivity in identifying HER2-positive tumor samples and 92.3% specificity in ruling out HER2 positivity in tumor samples that had the normal number of copies of the HER2 gene. Patients with more than the normal number of copies of the HER2 gene are considered candidates for trastuzumab therapy, whereas those with the normal number are not.
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Dr. Harish Malik