Squamous cell carcinoma of the tongue arising in lichen planus: a case report and review of the literature.

Lichen planus is a relatively common inflammatory disorder of unknown cause that affects the skin and mucosal surfaces. The relationship of oral lichen planus to oral squamous cell carcinoma is a matter of concern and debate. We present a case of squamous cell carcinoma of the dorsal surface of the tongue that arose in a previously biopsy-confirmed area of lichen planus. The literature on the development of oral cancer in patients with lichen planus is reviewed.