Does HPV type 16 or 18 Prevalence in Cervical Intraepithelial Neoplasia Grade 3 Lesions Vary by Age? An Important Issue for Postvaccination Surveillance

Abstract

We used existing data to investigate whether prevalence of HPV16/18 in cervical intraepithelial neoplasia 3 (CIN3) varies by age, in order to determine whether age specific baseline data is required as the prevaccination comparator for type-specific surveillance following HPV vaccination programs. We analyzed available Australian HPV typing data from 317 cervical smears from women with concurrent CIN3 on biopsy and conducted a review and analysis of the international literature. Among 317 women with CIN3, HPV16 was detected in 70% of those 16-25 years old, 59% of 26-35-year-olds and 48% of >36-year-olds (p = 0.025). This association took the form of a trend with decreasing HPV16 prevalence with increasing age (p = 0.007). That HPV16 is commoner in younger women with high-grade cervical lesions was consistent with all but one study of 18 identified in the literature. In screened populations, younger women with CIN3 are more likely to have HPV16 detected. To make valid pre- and post-vaccination comparisons, surveillance specimens for HPV typing should be both age stratified and lesion specific.