RESUMEN
In Brazil, the incidence of oral cavity cancer is estimated at 14,160 new cases in 2008. Contact endoscopy (stomatoscopy) applied to the oral cavity may favor early diagnosis. The aim of this study is to compare the contact endoscopy diagnosis to histological diagnosis of lesions of the lower lip vermilion area. Fifty-three prospective, ex vivo, non-consecutive lesions of the lip vermilion area were stained with toluidine blue solution, examined with stomatoscopy and directly biopsied. False-negatives did not occur and false-positives represented 9.4 percent. Sensitivity to diagnosis of malignancy was 100 percent, specificity was 88 percent, positive predicted value was 70.5 percent, negative predictive value was 100 percent and accuracy was 90.3 percent. Sensitivity and specificity of the contact endoscopy were high and the positive predictive value in relation to diagnosis of malignant lesions was good. Thus, stomatoscopy may be useful to diagnose lesions of the lower lip vermilion area.