Histologic changes associated with the topical use of isotretinoin on oral lichen planus

Abstract

B 0th systemic and topical synthetic retinoids (vitamin A derivatives) have been used extensively in the treatment of keratotic skin diseases that feature abnormal epithelial cell proliferation and differentiation. Dramatic results have been reported following the treatment of psoriasis and acne with etretinate and isotretinoin (13~cis retinoic acid).‘-4 Because of the antikeratinizing and immunomodulating effects of retinoids,‘.4*s the use of these compounds has been extended to the treatment of patients with cutaneous and oral lichen planus. Systemic retinoids-etretinate, isotretinoin, and tretinoin (all-trans retinoic acid)-have produced clinically significant results in patients with oral lichen planus.‘-l3 In one study, however, only marginal improvement was noted in patients with erosive lichen planus. I4 Because of side effects, the investigators thought that treatment with systemic etretinate did not justify the results. Topical tretinoin has produced generally good results in patients with oral lichen planus, without the complications of cheilitis, dry skin, eievation of serum liver enzymes, and elevation of serum triglycerides and cholesterol that are commonly associated with systemic therapy. ‘. ‘w’ Until recently, studies using topical agents have been limited to the use of tretinoin. A related retinoid-isotretinoin-had been made available to us in a 0.1% gel for clinical testing and showed considerable efficacy in the treatment of oral lichen planus. I8 Atrophic and erosive lesions responded less dramatically than reticular lesions. This double-blind clinical trial spanned 8 weeks of twice-daily application of isotretinoin gel (Figs. 1