Histologic differential diagnostic problems for oral discoid lupus erythematosus.

Biopsies of oral lesions from 21 patients with diagnostic skin lesions of discoid lupus erythematosus and from 21 patients with oral lichen planus and leukoplakia were examined blindly by light microscopy. The correct histologic diagnosis (DLE) was established in less than half of the cases. In one-third of the cases differentiation between DLE and lichen planus could not be made. In the rest of the cases histologic diagnoses other than DLE were stated. The study shows the need for better diagnostic methods for oral lesions.