Carcinogenic HPV prevalence and age-specific type distribution in 40,382 women with normal cervical cytology, ASCUS/LSIL, HSIL, or cervical cancer: what is the potential for prevention?

Background Assessment of the prevaccination type-specific prevalence of human papillomavirus (HPV) in the general population is important for the prediction of the impact of HPV vaccination. We collected consecutively residual specimens from liquid-based cytology samples from 40,382 women from the general population in Copenhagen, Denmark, during 2002-2005. All samples were tested for high-risk HPV using the Hybrid Capture 2 technique, and genotyping was done using LiPa (Innogenetics). Through linkage with the Pathology Data Bank, we obtained information on the cytology result, and histology if any, on all women. The participants were 14-95 years of age (median age 37 years) at enrollment. The overall prevalence of HR HPV was 20.6 % ranging from 46.0 % in 20-23-year-old women to 5.7 % in women 65 years or older. Independently of cytology/histology, HPV16 was the most prevalent type. For virtually all HPV types, the occurrence of CIN3+ was higher when the specific HPV type was present together with HPV16 than it was together with other high-risk HPV types than HPV16 or if the HPV type occurred as a single infection. The prevalence of HPV16 and/or HPV18 was 74 % in cervical cancer and the corresponding prevalence of HPV16/18/31/33/45/52/58 was 89 %. This study forms a valuable starting point for monitoring the effect of HPV vaccination in Denmark. In addition, the particular carcinogenic role of HPV16 and 18 is confirmed and may support a role of genotyping for HPV16 and 18 in cervical cancer screening.