Diagnostic Immunohistochemistry: what can go wrong?

Although immunohistochemistry (IHC) has become an integral component of the surgical pathology laboratory and practice, it remains a subspecialty in search of a definition. The rapid expansion of this discipline is continually contributing to the struggle of interested pathologists and technologists to identify the proper working conditions of antibody reagents and the right choice of detection systems and instrumentations. Training programs have not, for the most part, successfully incorporated IHC in their curricula. Thus, pitfalls in diagnostic IHC, in our opinion, are becoming more frequent than they used to. In this review, we highlight and attempt to provide solutions for the most common pitfalls in diagnostic IHC as it relates to the routine practice of surgical pathology.