Oncogenic human papillomavirus infection and cervical lesions in aboriginal women of Nunavut, Canada

Background. The high rate of cervical cancer among aboriginal women of nort hern Canada has prompted the search for more aggressive methods to augment Papanicolaou (Pap) screening in this population. Nearly all cervical cancer s result from oncogenic human papillomavirus (HPV) infections. This has gen erated interest for incorporating HPV testing into the current screening pr ogram. Goals: To determine the prevalence of oncogenic HPVs in Nunavut, and to ass ess the association between HPV and squamous intraepithelial lesions (SIL). Study Design: A cross-sectional study was conducted on the Pap-screened pop ulations in 19 communities of Nunavut, Canada. Liquid-based cytology was us ed to screen for SIL. HPV testing was performed using the Hybrid Capture II assay. Correlates of HPV infection and SIL were assessed by logistic regre ssion with control for potential confounders. Results: In 1290 women ages 13 to 79 years, the prevalence rate was 26% for oncogenic HPV and 6.9% for SIL. The odds ratio for the association between HPV and SIL was 37.9 (95% CI, 17.7-80.8) after multivariate adjustment. Th is association increased markedly with increasing viral load. More than 90% of the women with squamous intraepithelial lesions had positive test resul ts for HPV. More than 75% of the women who had positive test results for HP V but negative test results for SIL were younger than 30 years. Conclusion: The results of this study form the basis for further evaluation of the role that liquid-based cytology and HPV testing plays and will cont ribute to the strategy for cervical cancer prevention in Nunavut.