Keynote Message

Immunohistochemistry (IHC) is a complex technique which, put simply, employs the use of commercial antibodies to identify antigens (molecular markers) in tissue sections. The use of IHC in veterinary medicine has grown significantly over the last 20 years and, while once primarily utilized in diagnostics for further characterization of neoplastic processes, has evolved for use in prognostication as well as in research for the elucidation of pathogenesis of disease processes. Following an introduction to basic concepts of IHC, this session will focus on IHC application in cancer diagnostics. Cell-specific markers of various tumor types will be addressed, as will the pros and cons of individual versus panels of immunohistochemical stains. Fundamental aspects of IHC to include controls, appropriate interpretation, and understanding recommendations or results provided on the biopsy report, as well as limitations of IHC will also be discussed.

Key References

1.  Ramos-Vara JA, Miller MA. When tissue antigens and antibodies get along: revisiting the technical aspects of immunohistochemistry - the red, brown, and the blue technique. Vet Pathol. 2014;51(1):42–87. DOI: 10.1177/0300985813505879.

2.  Giuffrida MA, Bacon NJ, Kamstock DA. Use of routine histopathology and factor VIII-related antigen/von Willebrand factor immunohistochemistry to differentiate primary hemangiosarcoma of bone from telangiectatic osteosarcoma in 54 dogs. Vet Comp Oncol. 2016 Aug 9 [Epub ahead of print]. DOI: 10.1111/vco.12259.

3.  Ehrhart EJ, Kamstock DA, Powers BE. The pathology of neoplasia. In: Withrow SJ, Vail DM, Page RL, eds. Small Animal Clinical Oncology. 5th ed. St Louis, MO: Elsevier Saunders;2013:51–67.