Does HPV type 16 or 18 prevalence in cervical intraepithelial neoplasia grade 3 lesions vary by age? An important issue for postvaccination surveillance

Abstract

AIM: 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. MATERIALS & METHODS: 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. RESULTS: 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. CONCLUSION: 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.