Analysis of the anatomical distribution of HPV genotypes in head and neck squamous papillomas

Squamous papillomas (SPs) of the head and neck are usually benign lesions associated with human papilloma virus (HPV) infection. However, the reported HPV detection rates vary widely, especially with respect to anatomical distribution. The etiology of SPs in the head and neck remains unclear; analyzing HPV genotypes of SPs based on anatomical sites could assist in clarifying the pathogenesis of SPs in the head and neck. Therefore, the aim of this study was to review the prevalence, subtypes, and anatomical distribution of HPV in head and neck SPs at a hospital in China; we also investigated whether p16, a marker of HPV infection in oropharyngeal carcinoma, could serve as a surrogate marker for HPV in head and neck SPs. The presence of HPV DNA of 23 types (5 low-risk HPV and 18 high-risk HPV types) was detected via real-time PCR. p16 immunohistochemistry was performed using SP sections. Age, sex, anatomical location, and HPV subtype were recorded for each case. In total, 105 SPs were identified, including 47 in the larynx, 42 in the pharynx, 6 in the external auditory canal (EAC), 5 in the oral cavity, and 5 in the nasal cavity. HPV was found in 57 (54.3%) cases, with the highest positivity rate in the larynx (46/47; 97.9%). Only 5/42 (11.9%) patients showed HPV positivity in the pharynx. HPV incidence was highly dependent on the anatomical site. SPs in the larynx and EAC were more likely to carry HPV than those in other anatomical sites. High-risk HPV infections were rarely associated with SPs in the head and neck region. The sensitivity and specificity of p16 immunohistochemistry for HPV infection were 88% and 96%, respectively. There may be an association between p16 and HPV infection in head and neck SPs, but further studies are needed to validate this assertion.