Viral load of human papillomavirus and risk of CIN3 or cervical cancer.

Carcinogenic human papillomaviruses (HPV) are thought to be necessary for development of cervical cancer. We assessed whether higher viral loads of such viruses predicted future risk of CIN3 or cancer (CIN3+) in a cohort of 20810 women followed up for 10 years with cytological screening. We measured the viral load for 13 types of carcinogenic HPV (relative light units normalised to 1 pg/mL HPV 16 positive controls [RLU/PC]) using Hybrid Capture 2 testing of cervicovaginal lavages obtained at enrolment. Results were stratified into four groups (RLU/PC 1 to <10, 10 to <100, 100 to <1000, > or = 1000). Although presence of HPV strongly increased risk of CIN3+, high viral load did not further predict risk of CIN3+.