Validating the analytical power and parameters of an immunohistochemical test

As earlier stated by Clive R. Taylor, "immunohistochemistry is technically complex, and no aspect of this complexity can be ignored, from the moment of collecting the specimen to issuance of the final report". This chapter takes the reader through the elements of validating the analytical power of a cancer diagnostic assay - the immunohistochemical test. Issues related to the aim of the analytical validation, assay robustness, inter-run precision, intra-laboratory and inter-laboratory precision as well as internal and external quality assurance are presented. In addition, biomarker interpretation and quantification and especially the lack of standardisation within this area are discussed.