A case of tongue squamous cell carcinoma with Pseudoepitheliomatous hyperplasia.

A 52-year-old man with squamous cell carcinoma (SCC) complicated with pseudoepitheliomatous hyperplasia on the tongue is reported. Six times biopsies obtained from the tumors of the dorsal aspect of the tongue revealed no malignant changes in the hypertrophic epidermis. Histological findings of lichen planus were observed on a part of the tumors. Dental crowns containing patch test-positive mercury were irritating the ulcerating portion of the tumors. Serum SCC antigen level was elevated. The tumors regressed by administration of etretinete, but serum SCC antigen level was unchanged. After stopping the administration, the tumors proliferated again. Histological findings of SCC were observed in a biopsy sample obtained from the floor of the tongue. Serum SCC antigen was decreased after the tumors were resected. Lichen planus or irritations by dental crowns might have caused the SCC. Tongue carcinoma preferentially appears on the side and floor of the tongue. We have to be nervous to the biopsy site of tongue tumors.