Lichen sclerosus of the lip.

Lichen sclerosus is a chronic inflammatory mucocutaneous disorder predominately affecting prepubertal girls and postmenopausal women. Isolated lichen sclerosus affecting the oral mucosa is exceedingly rare. Only 13 patients with biopsy-proved isolated oral disease have been reported in the literature. We report a 10-year-old Caucasian girl with a well-demarcated 1.5 cm x 1.2 cm atrophic white plaque with a violaceous border and focal telangiectases on the right inferior vermillion lip, extending on to the labial mucosa. No other cutaneous surfaces, including genitalia, were involved. Incisional biopsy of the plaque on the lip revealed a patchy lichenoid infiltrate of lymphocytes associated with sclerosis of the papillary dermis and a thinned epidermis consistent with a diagnosis of lichen sclerosus. Treatment with a short course of high potency topical corticosteroids likely prevented the progression of this lesion.