14^th Asia Pacific Pathology Congress

Biography

Biography: Ahmed M. Abdelaziz

Abstract

Immunohistochemistry (IHC) combines anatomic, immunologic, and biochemical techniques to identify specific tissue components using a specific antigen-antibody reaction labeled with a visible reporter molecule. This binding is then visualized through the use of various enzymes that are coupled to the antibodies being used. The enzyme acts on a chromogenic substrate to cause deposition of a colored material at the site of antibody-antigen bindings. IHC is not only critical for the accurate diagnosis of malignancies but also plays a pivotal role in prognostic evaluation (e.g., estrogen and progesterone receptors in breast cancer) and treatments strategies (e.g. Her2/neu in certain breast cancers).    It is recommended that hormone receptor and Her2/neu testing be done on all primary invasive breast carcinomas and on recurrent or metastatic tumors.   If hormone receptors and Her2/neu are both negative on a core biopsy, repeat testing on a subsequent specimen should be considered, particularly when the results are discordant with the histopathologic findings.  Other biomarker tests (eg, Ki-67 or multigene expression assays) are optional and are not currently recommended for all carcinomas.  Guidelines published by the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP) require recording specific preanalytic and analytic variables that can affect test results. Information regarding assay validation or verification should be available in the laboratory. Any deviation(s) from the laboratory’s validated methods should be recorded. Appropriate positive and negative controls should be used and evaluated.