High-risk human papillomavirus types and squamous cell carcinoma in patients with respiratory papillomas

Respiratory papillomas (RPs) are benign, virally induced tumors of the larynx and respiratory epithelium that may obstruct the airway and tend to recur frequently. RPs are thought to be the result of infection with the human papillomaviruses (HPVs) types 6 and 11. We surveyed archival RP specimens to determine whether there were correlations of HPV type with patient characteristics or clinical course. Paraffin-embedded papilloma specimens of 45 different patients were analyzed. We assessed HPV types using the polymerase chain reaction with E6 consensus primers, hybrid capture assays (high or low risk), and dot blot hybridization of generic E6 PCR products with E6 type-specific oligonucleotide probes. The presence and type of HPV were correlated with patient data from a retrospective chart review. We found that RPs may have either low- or high-risk HPV types and some contain multiple HPV types. Respiratory infection with high-risk HPV apparently introduces a long-term risk of squamous cell carcinoma development, even in the absence of conventional cofactors. Low-risk HPV infection may also act in association with these cofactors to promote carcinogenesis. Our data also show a racial imbalance in RP that may indicate a difference in genetic resistance and/or susceptibility to HPV infection and the development of RP.