Human Papillomavirus in Oral Leukoplakia, Verrucous Carcinoma, Squamous Cell Carcinoma, and Normal Mucous Membrane.

OBJECTIVES Squamous cell carcinoma (SCC) is the most common oral malignancy, and verrucous carcinoma (VC) is a less invasive type of SCC. Leukoplakia (LP) is the most frequent premalignant lesion in the oral cavity. The human papillomavirus (HPV) has been recognized as one of the etiologic factors of these conditions. The association of anogenital and cervical cancers with HPV particularly its high-risk subtypes (HPV HR) has been demonstrated. The purpose of our study was to investigate the hypothetical association between HPV and the mentioned oral cavity lesions. METHODS One hundred and seventy-three samples (114 SCCs, 21 VCs, 20 LPs) and 18 normal mucosa samples (as a control group) were retrieved from the Department of Oral and Maxillofacial Pathology of Mashhad Dental School, Iran. The association of HPV genotypes in LP, VC, and SCC was compared to normal oral mucosa using the polymerase chain reaction. RESULTS The results showed the absence of HPV in normal mucosa and LP lesions. In three samples of VC (14.3%), we observed the presence of HPV HR (types 16 and 18). All VCs were present in the mandibular ridge of females aged over 65 years old. No statistically significant correlation between HPV and VC was observed (p=0.230). Additionally, 15 (13.1%) SCCs showed HPV positivity, but this was not significant (p=0.830). The prevalence of SCC was higher on the tongue with the dominant presence of less carcinogenic species of HPV (types 6 and 11). A statistically significant association was not observed between HPV and SCC or VC in the oral cavity. CONCLUSION More studies are necessary to better understand the relationship between HPV and malignant/premalignant oral cavity lesions.