Immunohistochemistry as an Indispensable Tool in Oncology

Immunohistochemistry (IHC) is a process of detecting antigens in tissues by utilizing the principle of specific antigens-antibody binding. It is described as the localization of antigens in histological and cytological (immunocytochemistry) preparations by exploiting specific antigen/antibody interactions which result in the attachment of a marker to the antigen. Even though conventional histopathology is central to cellular pathology diagnosis and has brought about marked development in general pathology over the years, it is undermined by errors in interpretation and limited detection of the majority of proteins, enzymes and some of the tissue structures that are central to certain diagnoses.

The utilization of immunologic reactions and histochemistry complex brought significant improvements in the microscopic diagnosis of lesions and cancer. Its inexpensiveness, utilization of small tissues such as core needle biopsies and fine needle aspirates, detection and localization of a wide variety of biomarkers with near-perfect accuracy, sensitivity and staining quality, make it a better diagnostic tool that covers the limitation of conventional histopathological methods and hence, employed as a secondary supportive technique in most routine diagnostic laboratories to ensure accurate diagnosis.

This review aims to provide a general overview of IHC including its merits, methods, and applications in clinical and research laboratories.