Primary human papillomavirus DNA screening for cervical cancer prevention: Can the screening interval be safely extended?

Cytological screening has substantially decreased the cervical cancer incidence, but even better protection may be achieved by primary high-risk human papillomavirus (hrHPV) screening. In the Netherlands, five-yearly cytological screening for women aged 30-60 years will be replaced by primary hrHPV screening in 2016. The new screening guidelines involve an extension of the screening interval from 5 to 10 years for hrHPV-negative women aged 40 or 50 years. We investigated the impact of this program change on the lifetime cancer risks in women without an hrHPV infection at age 30, 35, 40, 45 or 50 years. The time to cancer was estimated using 14-year follow-up data from a population-based screening intervention trial and the nationwide database of histopathology reports. The new screening guidelines are expected to lead to a reduced cervical cancer risk for all age groups. The average risk reduction was 34% and was smallest (25%) among women aged 35 years. The impact of hrHPV screening on the cancer risk was sensitive to the duration from cervical intraepithelial neoplasia grade 2/3 (CIN2/3) to cancer; a small increase in the cancer risk was estimated for women aged 35 or 40 years in case a substantial proportion of CIN2/3 showed fast progression to cancer. Our results indicate that primary hrHPV screening with a ten-yearly interval for hrHPV-negative women of age 40 and beyond will lead to a further reduction in lifetime cancer risk compared to five-yearly cytology, provided that precancerous lesions progress slowly to cancer.