Detection of human papillomavirus DNA in formalin-fixed, paraffin-embedded squamous papillomas of the oral cavity

BACKGROUND: Squamous papillomas are exophytic proliferations of surface oral epithelium. Human papillomavirus (HPV) infection is widely accepted as the etiology of squamous papillomas however the virus cannot be detected in a significant percentage of lesions. MATERIAL AND METHODS: Using polymerase chain reaction (PCR), we tested 35 formalin-fixed paraffin-embedded (FFPE) squamous papillomas for the presence of HPV DNA. RESULTS: Six papillomas (17%) tested positive for HPV DNA; four contained HPV-6 and two contained HPV-11. Given that β–globin DNA was only identified in half of the samples, DNA degradation appears to have significantly impacted the results. CONCLUSIONS: The results likely represent an underestimation of the true number of HPV-positive specimens in our study. Potential explanations for HPV-negative squamous papillomas include transient HPV infection, failure of the experiment to detect HPV if present, or the possibility that some lesions may not result from HPV infection. Key words:HPV, PCR, FFPE, papilloma, oral.