Histological Classification of Cancer and Precancer of the Oral Mucosa 1. Carcinomas Squamous cell carcinoma Verrucous cell carcinoma Basaloid squamous cell carcinoma Adenoid squamous cell carcinoma Spindle cell carcinoma Adenosquamous carcinoma Undifferentiated carcinoma 2. Benign lesions capable of microscopically resembling oral squamous cell carcinoma and oral verrucous carcinoma Papillary hyperplasia Granular cell tumor Discoid lupus erythematosus Median rhomboid glossitis Keratoacanthoma Necrotizing sialometaplasia Juxtaoral organ of Chievitz Chronic hyperplastic candidiasis Verruciform xanthoma Verruca vulgaris Condyloma acuminatum 3. Precancerous lesions (Clinical classification) Leukoplakia Erythroplakia Palatal keratosis associated with reverse smoking 4. Precancerous lesions (Histological classification) Squamous epithelial dysplasia Squamous cell carcinoma in situ Solar keratosis 5. Benign lesions capable of r...