Seroreactivity to epidermodysplasia verruciformis-related human papillomavirus types is associated with nonmelanoma skin cancer.

DNA from epidermodysplasia verruciformis-related human papillomavirus (EV-HPV) types is frequently found in nonmelanoma skin cancer (squamous and basal cell carcinoma). Epidemiological studies that investigate the relation between EV-HPV infection and nonmelanoma skin cancer are scarce. We designed a case-control study in which we looked for HPV infection in 540 cases with a history of skin cancer and 333 controls. By measuring seroreactivity to L1 virus-like particles of EV-HPV types 5, 8, 15, 20, 24, and 38 and the genital type HPV16 and by estimating the skin cancer relative risk among HPV seropositives, we analyzed whether EV-HPV serorecognition is associated with nonmelanoma skin cancer. Seroreactivity to five of the six EV-HPV types tested (HPV5, 8, 15, 20, and 24) was significantly increased in the squamous cell carcinoma cases. After adjusting for age and sex, the estimated squamous cell carcinoma relative risk was significantly increased in HPV8 and HPV38 seropositives [odds ratio (OR) = 14.7 (95% confidence interval (CI), 1.6-135) and OR = 3.0 (95% CI, 1.1-8.4), respectively]. The estimated relative risk for nodular and superficial multifocal basal cell carcinoma was also significantly increased in the HPV8 seropositives [OR = 9.2 (95% CI, 1.1-78.2) and OR = 17.3 (95% CI, 2.1-143), respectively] and in the HPV20 seropositives [OR = 3.2 (95% CI 1.3-7.9) and OR = 3.4 (95% CI 1.2-9.5), respectively]. The relative risk of developing malignant melanoma was not increased among HPV seropositives, and no associations were found for HPV16. Restricted analyses among the HPV seropositives only, to exclude distortion by interindividual differences in seroresponsiveness, underscored the significance of our findings. Restricted analyses among patients with skin cancer only, however, revealed that EV-HPV seropositivity was not significantly more present in patients with nonmelanoma skin cancer than in those with melanoma skin cancer. Taken together, our results indicate that EV-HPV serorecognition is nonspecifically associated with nonmelanoma skin cancer and suggest that EV-HPV-directed seroresponses are induced upon skin cancer formation, rather than upon infection.