Sequential immunopathologic study of oral lichen planus treated with tretinoin and etretinate.

Twenty-five patients with oral lichen planus confirmed by histologic examination were divided into three groups: 10 patients received topical treatment with tretinoin, 10 received systemic treatment with etretinate, and the five remaining patients, who received no treatment, served as a control group. An immunopathologic study with the use of monoclonal antibodies was carried out before and after the 3-month course of treatment and showed a variation in the distribution and phenotype of inflammatory cells. No difference between the two types of treatment was observed, but treated patients had a shorter evolution of the disease when compared with control patients.