HER2/ Testing In 432 Consecutive Breast Cancer Cases using FISH and IHC - A Comparative Study.

Introduction: The development of trastuzumab, a HER-2/ targeted monoclonal antibody resulted in significant improvements in clinical response and survival in HER-2/ gene amplified group of patients. Thus, accurate assessment of HER-2/ status becomes critical. Fluorescence In Situ Hybridization (FISH) and Immunohistochemistry (IHC) are the most commonly used methods for this purpose and specific recommendations exist with regard to the concordance to be observed between the two tests.