Changes in HPV prevalence in Danish women with vulvar cancer during 28 years – A nationwide study of >1300 cancer cases

• Published in: Gynecologic oncology 2022-09, Vol.166 (3), p.589-595
• Main Authors: Rasmussen, Christina Louise, Thomsen, Louise T., Baandrup, Louise, Franzmann, Maria Benedicte, Larsen, Lise Grupe, Madsen, Else Mejlgaard, Salinas, Nadia Villena, Schledermann, Doris, Winberg, Birgitte Hjelm, Ørnskov, Dorthe, Waldstrøm, Marianne, Kjaer, Susanne K.
• Format: Article
• Language: English
• Subjects: Human papillomavirus; Prevalence; Vulvar cancer
• ISSN: 0090-8258; 1095-6859
• DOI: 10.1016/j.ygyno.2022.06.014

A substantial proportion of vulvar cancers are caused by high-risk human papillomavirus (hrHPV), but hrHPV prevalence in vulvar cancer has mainly been investigated in smaller studies which did not evaluate time trends. Our aim was to assess hrHPV prevalence in >1300 Danish vulvar cancers diagnosed during 1990–2017, including changes in hrHPV prevalence over time. In a nationwide pathology register, we identified women diagnosed with vulvar cancer at thirteen hospitals from all Danish regions. Archival tumor tissue was collected from local repositories and, upon pathology review, sent to a central laboratory for HPV testing using INNO-LiPA. We calculated hrHPV prevalence according to time, age and histology, and evaluated the overall and age-specific estimated annual percentage change (EAPC). We included 1308 vulvar cancer cases, with a median age of 72 years at diagnosis. The overall hrHPV prevalence was 52.0% (95% CI: 49.3–54.7). HPV types 16/18 were found in 39.6% of cases, whereas nine-valent HPV (9vHPV) vaccine types 16, 18, 31, 33, 45, 52, and 58 were found in 50.8%. The hrHPV prevalence showed an increasing trend over time, with an EAPC of 0.35% (95% CI: 0.00–0.71). The hrHPV prevalence was higher in younger women throughout the study period, and increasing trends over time were seen in both older (age ≥ 60) and younger (age < 60) women. The hrHPV prevalence was higher in non-keratinizing (71.0%) and warty/basaloid (78.0%) carcinomas than in keratinizing (39.4%) and verrucous (36.4%) carcinomas. Our results indicate that the 9vHPV vaccine could potentially prevent a substantial proportion of vulvar cancers in Denmark. •We investigated the high-risk HPV prevalence in 1332 Danish vulvar cancer patients diagnosed during 1990–2017.•The overall high-risk HPV prevalence was 52%, with an increasing trend over time.•High-risk HPV prevalence was consistently higher in younger women during the 28 year study period.•More than half of vulvar cancers contained HPV types included in the nine-valent HPV vaccine.