Introduction to Immunohistochemistry

Im • mu • no • his • to • chem • is • try (n.) Microscopic localization of specific antigens in tissues by staining with antibodies labeled with fluorescent or pigmented material. Immunohistochemistry (IHC) is a method used to determine the expression of biomarkers in tissue. This educational guidebook will describe immunohistochemistry as it is used in the pathology laboratory as an aid in the differential diagnosis and classification of cancer, and for certain other diseases, including infections. The factors that influence the immunohis-tochemical staining result start in the surgery operating room and end at the interpretation of the stain by the pathologist, which ultimately leads to treatment decision by the oncologist. For those new to the world of immunohistochemistry here is a brief outline of the steps needed to localize antigens in tissues using antibodies for cancer diagnosis: Figure 1.1 From biopsy to reporting.