Interuniversity microscopic slide exchanges: a mechanism for peer review and continuing education in oral pathology.

One thousand seven hundred and three consecutive cases from a microscopic slide exchange with 10 institutions were evaluated for extent of agreement (or disagreement) defined as: A) complete agreement (85.8%). B) Disagreement--difference in diagnostic terminology, no significant pathologic or clinical implications (1.4%); C) disagreement--difference in diagnosis with pathologic significance only (7.7%); C1 disagreement--difference in diagnosis with pathologic significance only, radiographic interpretation necessary (1.1%); D) disagreement--major significance for prognosis and/or treatment (4.0%). Trends in disagreement were identified in the following tissue/location categories: mesenchymal lesions, minor salivary gland tumors, odontogenic tumors, fibro-osseous lesions, and benign epithelial lesions. These are discussed in relation to the oral pathology literature. All disagreements with significance for prognosis and/or patient treatment were evaluated retrospectively in an attempt to resolve the disparities. The implications for peer review, continuing education, and teaching programs are addressed.