Viral gene detection in oral neoplasms using the polymerase chain reaction

Eighty-four squamous cell proliferative lesions of the oral cavity and six examples of normal oral squamous mucosa were investigated for the presence of human papillomavirus (HPV) by the polymerase chain reaction (PCR) using universal primers and type specific probes. Human papillomavirus was identified in 1 of 6 histologically normal biopsy specimens, 2 of 4 hyperplasias, 2 of 5 inflammatory lesions, 9 of 36 cases of dysplasia or carcinoma in situ, and 7 of 39 carcinomas. All of the specimens found positive for HPV using the PCR were confirmed using slot blot hybridizations. All HPV-positive cases contained HPV 16. In addition, 2 were co-infected with HPV 11 and 1 was co-infected with HPV 18. Types 6 and 33 were not found. The same genotypes that infect the uterine cervix also were found in the oral cavity. This is the first time universal primers that allow for the detection of HPV types 6, 11, 16, 18, 31, 33, 35, 39, 40, 42, 45, 51-59, and at least 25 other novel types have been used on oral tumors, and represents the largest number of oral samples analyzed by the PCR at this time. Due to lack of clear correlation between HPV infection and histologic findings, however, the role of this virus in oral carcinogenesis remains uncertain.