What is the role of immunohistochemistry in tumor diagnosis?

The role of immunohistochemistry (IHC) in tumor diagnosis predominantly involves the identification of specific cell types and the detection of proteins within tissues. This technique utilizes antibodies that bind to specific antigens or proteins present in the tumor cells. By applying these antibodies to tissue sections and visualizing the binding through various detection methods, IHC allows pathologists to determine the presence or absence of certain biomarkers. This is particularly crucial in the diagnosis of different tumor types and subtypes, as many cancers express unique protein markers.

Understanding these specific markers helps in making informed decisions regarding prognosis and treatment. For example, the presence of specific receptors may guide the use of targeted therapies. Furthermore, IHC contributes to distinguishing between different types of tumors that may have overlapping histological features, thus providing essential information on the tumor's origin and characteristics.

While the other choices may seem relevant, they do not accurately capture the primary function of immunohistochemistry in the context of tumor diagnosis. Measuring tumor size pertains more to imaging studies, determining genetic makeup relates to molecular diagnostic techniques rather than IHC, and assessing overall patient health falls outside the specific diagnostic focus of IHC.