Cytologic diagnosis of dysplasia in the alimentary tract.

Diagnosis of dysplasia in the gastrointestinal tract has important clinical implications for management decisions. Although dysplasia is generally recognized by histology, cytologic specimens have been shown to increase the sensitivity of tissue diagnosis. The advantage of cytology is the ability to sample a much larger mucosal area. The relatively low specificity caused by the overlap in cytologic features of reactive atypia, dysplasia, and carcinoma is a disadvantage. This article reviews the cytology of squamous and glandular dysplasia in the alimentary tract as well as the studies that have evaluated the clinical utility of cytologic sampling of the gastrointestinal tract in the evaluation of dysplasia.