1 Quality assurance in immunohistochemistry

Abstract

Immunohistochemistry (IHC) can specifically detect individual epitopes and can discriminate cell types and their differentiation states with unique, accuracy. IHC has allowed an increased diagnostic sensitivity, reliability, and reproducibility of diagnoses rendered by the pathologist. It is now widely applied as an immediate aid to diagnosis in a wide range of settings. It is used to solve problems in the differential diagnosis and allows a diagnosis to be rendered on specimens formerly regarded as inadequate. To some extent, it may compensate for morphologic experience and skill. In addition, it may be useful to determine the likely origin of carcinomas. Of growing importance is the need for IHC to provide prognostic information for biology-based therapeutic approaches. Initially, IHC served to obtain accurate information from histologic specimens. With growing possibilities, expectations from IHC have also increased. Now, the diagnosis, prognostic judgment, and therapy are based on IHC to such an extent that patient care is influenced by the reliability of immunohistochemical stains. To be confident in their results, it is therefore necessary to perform quality controls on IHC itself. IHC was initially a tool for quality control, but now it has become its subject.