The role of cytology in oral lesions: a review of recent improvements.

Historically, sensitivity and specificity of oral cytology is poor. Using conventional oral cytology for the diagnosis of cancer and its precursors has not had the success that cytologists had hoped for; however, with improved methodology, oral cytology has enjoyed a resurgence of interest. This renewed interest is partly due to the introduction of a specialized brush that collects a full-thickness epithelial sample and not just superficially sloughed cells, as well as analysis of that sample with computer assistance; in addition, a variety of adjunctive techniques have been introduced to potentially enhance the diagnosis of the cytologic specimens including DNA analysis, immunocytochemistry, molecular analysis, and liquid-based preparations. An increase in sensitivity (>96%) and specificity (>90%) of the oral brush biopsy with computer-assisted diagnosis has been reported for identification of malignant and premalignant lesions. Brush cytology is valuable to prevent misdiagnosing doubtful oral lesions, i.e., those lesions without a definitive etiology, diagnosing large lesions where excision of the entire tissue is not possible or practicable, evaluating patients with recurrent malignancies, and monitoring premalignant lesions.