Low prevalence of human papillomavirus infection in sinonasal inverted papilloma and oncocytic papilloma.

The aim of this study was to investigate the role of human papillomavirus (HPV) in sinonasal inverted papilloma (SIP) and sinonasal oncocytic papilloma (SOP) from a single institution and whether p16 can serve as a surrogate marker for HPV infection. This study included 49 subjects with SIP and 36 subjects with SOP. Formalin-fixed paraffin-embedded tissues were used to extract genomic DNA, and HPV detection was performed by utilizing a valid nested polymerase chain reaction approach that can detect all known HPV subtypes. Immunohistochemistry was used to evaluate the expression of p16 in all tumor sections. The presence of HPV DNA was found in 6.1% (3/49) of the SIP patients and 11.1% (4/36) of the SOP patients. All identified HPV subtypes in SIP were high-risk HPV, including HPV-16 (two patients) and HPV-58 (one patient). Regarding SOP, there were three patients positive for HPV-16 and one with low-risk HPV (type 6). In total, 11/49 (22.4%) SIP lesions and 10/36 (27.8%) SOP lesions were considered p16 positive, with p16 staining in more than 70% of tumor cells. There was only one SIP and one SOP that were positive for both HPV (high-risk HPV type 16) and p16 staining. HPV does not play an etiologic role in inverted papilloma or oncocytic papilloma of the sinonasal region. p16 immunostaining should not be used as a surrogate marker to evaluate the HPV infection status in these lesions.