A cervical screening initiative for elderly women in Denmark

Introduction: To assess outcome of a one-time human papillomavirus (HPV)-screening in 2017 of Danish women aged 70+.

Material and methods: Women born 1947 or before were personally invited to have a cell-sample collected by their general practitioner. Screening- and follow-up samples were analyzed in hospital laboratories in the five Danish regions and registered centrally. Follow-up procedures varied slightly across regions. Cervical intraepithelial neoplasia 2 (CIN2) was recommended treatment threshold. Data were retrieved from the Danish Quality Database for Cervical Cancer Screening. We calculated CIN2+ and CIN3+ detection rates per 1000 screened women, and number of biopsies and conizations per detected CIN2+ case. We tabulated annual number of incident cervical cancer cases in Denmark for the years 2009-2020.

Results: In total, 359 763 women were invited of whom 108 585 (30% of invited) were screened; 4479 (4.1% of screened, and 4.3% of screened 70-74 years) tested HPV-positive; of whom 2419 (54% of HPV-positive) were recommended follow-up with colposcopy, biopsy and cervical sampling, and 2060 with cell-sample follow-up. In total, 2888 women had histology; of whom 1237 cone specimen and 1651 biopsy only. Out of 1000 screened women 11 (95% confidence interval [CI]: 11-12) had conization. In total, 579 women had CIN2+; 209 CIN2, 314 CIN3, and 56 cancer. Out of 1000 screened women five (95% CI: 5-6) had CIN2+. Detection rate of CIN2+ was highest in regions where conization was used as part of first-line follow-up. In 2009-2016, number of incident cervical cancers in women aged 70+ in Denmark fluctuated around 64; in 2017 it reached 83 cases; and by 2021 the number had decreased to 50.

Conclusions: The prevalence of high-risk HPV of 4.3% in women aged 70-74 is in agreement with data from Australia, and the detection of five CIN+2 cases per 1000 screened women is in agreement with data for 65-69 year old women in Norway. Data are thus starting to accumulate on primary HPV-screening of elderly women. The screening resulted in a prevalence peak in incident cervical cancers, and it will therefore take some years before the cancer preventive effect of the screening can be evaluated.