Verrucous carcinoma occurring in a lesion of oral lichen planus.

Verrucous carcinoma of the oral cavity is relatively rare. Well-documented associations include human papillomavirus and carcinogens such as tobacco. Less well understood is the association with chronic inflammation, such as seen in lichen planus. Verrucous carcinoma has previously been described occurring in lesions of lichen planus of the foot and penis. We report the first case, to our knowledge, of verrucous carcinoma occurring in a lesion of oral lichen planus.