Human papillomavirus-associated oral intraepithelial neoplasia

This study evaluated an unusual subset of oral epithelial dysplasia for the presence of transcriptionally active high-risk HPV subtypes and to further characterize the histological criteria for this condition. There were 20 cases diagnosed as epithelial dysplasia with marked apoptosis of the anterior oral cavity. Clinical and follow-up data were collected and histopathological features were documented. Immunoperoxidase studies were performed for p16 and in situ hybridization studies were performed for low- and high-risk HPV sub-types. Gender- and site-matched controls of conventional moderate-to-severe oral epithelial dysplasia were similarly evaluated using immunoperoxidase studies for p16 and in situ hybridization; the number of apoptotic cells for study and control cases was counted at two different tissue sites. There were 17 men and 3 women with a median age of 56 years. Seventeen lesions were described as white and five were described as rough or papillary. Thirteen were located on the lateral or ventral tongue, some extending onto the floor of the mouth. Epithelial hyperplasia with marked karyorrhexis and apoptosis were present in all the cases, along with features of conventional oral epithelial dysplasia. A statistically significant number of apoptotic cells were identified in the study cases when compared with controls (P>0.0001). Twenty cases were positive for high-risk HPV by in situ hybridization and all 19 nineteen cases evaluated for p16 demonstrated overexpression. Two patients were diagnosed with squamous cell carcinomas and one patient developed recurrent disease. We report a subset of oral epithelial dysplasia that occurs mostly in adult men on the ventral or lateral tongue and is positive for high-risk HPV and for p16. We propose use of the term 'HPV-associated Oral Intraepithelial Neoplasia' to characterize these lesions of the oral cavity for consistency in nomenclature with HPV-associated lesions of the lower anogenital tract. One case recurred and one developed invasive cancer.