Predictive value of immunohistochemistry in pre-malignant lesions of the gastrointestinal tract.

Immunohistochemistry can be an important adjunct to histopathology for the diagnosis of pre-malignant lesions of the gastrointestinal tract and in patient risk stratification. The purpose of this review is to provide information and guidance on the usefulness of immunohistochemical markers that facilitate the diagnosis of dysplasia and help to predict risk for the development of carcinoma in pre-malignant lesions of the gastrointestinal tract. Particular emphasis is given to the role of immunohistochemistry in the assessment of epithelial dysplasia in the setting of Barrett's esophagus and inflammatory bowel disease; supplementary immunohistochemistry for subtyping adenomas of the stomach and ampulla and serrated polyps of the colon and rectum; and ancillary markers of squamous neoplasia of the anal canal.