The efficacy of human papillomavirus vaccination in young Japanese girls: the interim results of the OCEAN study

Clinical impact of age‑specific distribution of combination patterns of cytology and high‑risk HPV status on cervical intraepithelial neoplasia grade 2 or more

To the best of our knowledge, the present study is the first to elucidate the significance of cytology and high-risk human papillomavirus (hrHPV) status in different age groups for the detection of cervical intraepithelial neoplasia (CIN)2, CIN3 and squamous cell carcinoma (SCC). There were 12 combinations based on cytology and hrHPV status [cytology: Atypical squamous cells (ASC) of undetermined significance, low-grade squamous intraepithelial lesion, ASC not excluding high-grade squamous intraepithelial lesion (HSIL) and HSIL; hrHPV status: HPV16/18-positive (16/18+), hrHPV positive for subtypes other than 16/18 (others+) and hrHPV-negative (hrHPV-)]. All patients were categorized into four groups based on age (18-29, 30-39, 40-49 and ≥50 years). For patients with CIN2, CIN3 and SCC (CIN2+) (n=107), the distribution of cytology and hrHPV was investigated in each age group. In addition, for all patients (n=446), the occurrence of CIN2+ in each of the 12 combinations was investigated in each age group. In the 18-29-year age group, the most common combination was HSIL and 16/18+, followed by HSIL and others+, which accounted for 73% of CIN2+ cases. The occurrence of HSIL and 16/18+ decreased with increasing age, and no cases occurred in the 50-year age group. In the 18-29-year age group, all patients with HSIL and 16/18+ were diagnosed with CIN2+. CIN2+ was predominantly detected in patients with HSIL in the 18-29-year age group, as well as hrHPV- and others+. This definite distinction was not observed in any other age group. For CIN2+, the distribution patterns of cytology and hrHPV status combinations varied significantly among different age groups. Accordingly, the clinical impact of the combination of cytological findings and hrHPV status can vary among age groups.

Effects of the Prophylactic HPV Vaccines on HPV Type Prevalence and Cervical Pathology

Vaccination programs with the current prophylactic HPV vaccines started in most countries around 2008 with introduction of the bivalent Cervarix HPV16/18 vaccine, rapidly followed by Gardasil (HPV6/11/16/18) and, finally, Gardasil 9 (HPV6/11/16/18/31/33/45/52/58), from 2015. Many studies have now confirmed their ability to prevent infection with vaccine-covered HPV types, and the subsequent development of either genital warts and/or cervical neoplasia, although this is clearly more effective in younger women vaccinated prior to sexual debut. Most notably, reductions in the prevalence of vaccine-covered HPV types were also observed in unvaccinated women at the same geographical location, presumably by sexual dissemination of these changes, between vaccinated and unvaccinated women. Furthermore, there are several studies that have demonstrated vaccine-associated HPV type-replacement, where vaccine-covered, high-risk HPV types are replaced by high-risk HPV types not covered by the vaccines, and these changes were also observed in vaccinated and unvaccinated women in the same study population. In light of these observations, it is not entirely clear what effects vaccine-associated HPV type-replacement will have, particularly in older, unvaccinated women.