Prevalence Of High-Risk Human Papillomavirus In Uterine Cervical Lesions Among Older Japanese Women.

5084 Background: To estimate the prevalence and genotypes of high-risk human papillomavirus (HPV) among older Japanese women, using liquid-based cytology (LBC). Methods: ThinPrep LBC specimens were collected from 11,039 Japanese women (age range, 14-98 years). After classifying cytodiagnosis, specimens were analyzed for HPV DNA using the multiplex polymerase chain reaction method. Cervical smear specimens from 1,302 women showed positive results. To examine the prevalence of HPV in women defined as negative for intraepithelial lesion or malignancy (NILM), 2,563 samples were randomly selected from the remaining 9,737 women. Comparisons were made between women ≥50 years of age (older age group) and women <50 years of age (younger age group). Written informed consent was obtained from all patients. In this study, the high-risk HPV genotypes encountered were 16, 18, 31, 33, 35, 45, 52, and 58. Results: In the older age group with abnormal smear findings, HPV genotypes were detected in 49.7% (148/298), including high-risk HPV genotypes in 40.9% (122/298). In the younger age group with abnormal smear findings, HPV genotypes were detected in 71.7% (720/1004), including high-risk HPV genotypes in 58.1% (583/1,004). In NILM, HPV-positive rates were 4.5% (39/873) in the older age group and 11.8% (199/1,690) in the younger age group. In high-grade squamous intraepithelial lesion (HSIL) or more severe cytological findings, HPV genotypes of each group (older age group/younger age group) were detected in 61.7%/83.1%, and high-risk HPV genotypes were detected in 56.4%/74.7% of women. In positive cervical smears, HPV 16 was the most frequently detected (28.5%) in the younger age group, while HPV 52 (31.3%) and 58 (27.2%) were detected more frequently than HPV 16 (18.4%) in the older age group. Conclusions: In Japan, although HPV infection as a cause of abnormal cervical cytology is more frequent among younger age groups than in older age groups, high-risk HPV infection was more highly associated with older individuals (older age group/younger age group: abnormal smear findings, 82.4%/81.0%; HSIL or more severe cytological findings, 91.3%/89.9%). In older age groups, HPV 52 and 58 were more frequent than HPV 16.