Human papillomavirus types in cervical high-grade lesions or cancer among Nordic women - Potential for prevention

Publisher's version (útgefin grein)It is valuable to establish a population‐based prevaccination baseline distribution of human papillomavirus (HPV) types among women with high‐grade cervical intraepithelial neoplasia (CIN) grade 2 or 3 and cervical cancer in order to assess the potential impact of HPV vaccination. In four countries (Denmark, Norway, Sweden, and Iceland), we collected consecutive series of cervical cancers (n = 639) and high‐grade precancerous cervical lesions (n = 1240) during 2004‐2006 before implementation of HPV vaccination and subjected the specimens to standardized HPV genotyping. The HPV prevalence was 82.7% (95% confidence interval [CI] 79.0‐86.4) in CIN2, 91.6% (95% CI 89.7‐93.5) in CIN3, and 86.4% (95% CI 83.7‐89.1) in cervical cancer. The most common HPV types in CIN2/3 were HPV16 (CIN2: 35.9%, 95% CI 31.2‐40.6; CIN3: 50.2%, 95% CI 46.8‐53.6) and HPV31 (CIN2: 10.9%, 95% CI 7.8‐13.9; CIN3: 12.1%, 95% CI 9.9‐14.3), while HPV16 and HPV18 were the most frequent types in cervical cancer (48.8%, 95% CI 44.9‐52.7 and 15.3%, 95% CI 12.5‐18.1, respectively). The prevalence of HPV16/18 decreased with increasing age at diagnosis in both CIN2/3 and cervical cancer (P < 0.0001). Elimination of HPV16/18 by vaccination is predicted to prevent 42% (95% CI 37.0‐46.7) of CIN2, 57% (95% CI 53.8‐60.5) of CIN3 and 64% (95% CI 60.3‐67.7) of cervical cancer. Prevention of the five additional HPV types HPV31/33/45/52/58 would increase the protection to 68% (95% CI 63.0‐72.2) in CIN2, 85% (95% CI 82.4‐87.2) in CIN3 and 80% (95% CI 77.0‐83.2) in cervical cancer. This study provides large‐scale and representative baselines for assessing and evaluating the population‐based preventive impact of HPV vaccination.We thank Cecilia Wahlström and Kia Sjölin for assistance with the HPV genotyping. SKK received lecture fee from Merck and Sanofi Pasteur MSD, scientific advisory board fee from Merck, and unrestricted research grants through her institution from Merck. JD reports having received research grants to his institution for the funding of the study. CM received lecture fees and travel grants from Sanofi Pasteur MSD. CL and MH report that their institution received a grant from Merck. KLL is a full‐time employee of Merck & Co. Inc and owns stocks and options of Merck. MN received research grants from MSD Norway/Merck through the affiliating institute. CDC, SG, LT, KS, and BTH report no conflicts of interest.Peer Reviewe

HPV infection in cervical and other cancers in Saudi Arabia: implication for prevention and vaccination

HPV is closely associated with cervical cancer that the incidence of this tumor is regarded as a surrogate marker for HPV infection in countries lacking epidemiological studies. HPV is also implicated in subsets of anogenital and oro-pharyngeal cancers. Although cervical cancer is the third most common cancer in women worldwide, its reported incidence is low in Saudi Arabia, ranking number 12 between all cancers in females and accounts only for 2.4% of all new cases, despite the lack of national screening programs. However, the limited available studies from Saudi Arabia indicate that HPV prevalence and genotypes’ distribution in invasive cervical cancer show similar pattern as in the world. Cytology screening (Pap Smear) and HPV vaccinations are the two preventive measures against cervical cancer. The two available vaccines are effective against the two most common HPV genotypes (HPV-16 and 18). Since 92% of cervical tumors in the Kingdom are infected with HPV of which 78% are HPV-16 and 18 genotypes, vaccination is expected to protect against more than two-third of cervical cancers in Saudi Arabia. Nevertheless, due to its low incidence (2.1/100,000 women), a proper cost-effectiveness analysis is required to justify the implementation of a costly vaccine bearing in mind that HPV could potentially be associated with about 3% of all cancers. However, further studies are needed to ascertain the real prevalence of HPV at the population level at large, its association with various types of cancers and also the impact of local tradition and emerging behavioral trends that could affect HPV transmission and consequently the effectiveness of applying national vaccination program