Piret Veerus

Prevalence of Human Papillomavirus Subtypes and Related Cytology in Estonian Cervical Cancer Screening Population in 2021

Introduction Prevalence of high risk human papillomavirus (hrHPV) and its subtypes by sociodemographic factors and the related cytological findings in the Estonian cancer screening population were examined, with the aim to improve cancer prevention. Methods This cross-sectional study included all women who participated in the Estonian cervical cancer screening programme from January 1, 2021 to January 31, 2022 and had a valid HPV test result reported to the Estonian Cancer Screening Registry (n = 37 537, aged 30, 35, 40, 45, 50, 55, 60, and 65). Limited sample (N = 18 784) within the total sample consisted of women who used self-sampling (N = 3535) or whose clinician collected sample was analysed using lab methodology that differentiates HPV16, 18, and 45. Data on HPV and cytology results were obtained from the Estonian Cancer Screening Registry, whereas data on education, nationality, and marital status were obtained from the Estonian Population Registry. Results hrHPV was detected in the samples of 3307 (8.8%) women, and the prevalence was significantly higher in age groups under 40, in women with lower education, of Estonian nationality, and with no partner. The overall prevalence of HPV16 was 1.8%, ranging from 4.4% in 30-year-old women to 0.9% in 55-year-old women. The proportion of normal cytology was 50% among all hrHPV positive women and 35% in all HPV16 positive women, while it was 47% for HPV16 alone and 24% for HPV16 plus other hrHPV subtypes. The probability of normal cytology was significantly higher in women aged 50 and older compared to women aged 30 and 35 for total hrHPV and HPV16. Conclusion All countries should monitor HPV prevalence across different age groups. As different HPV genotypes have a different oncogenic risk profile, extended or complete genotyping would help personalised risk-based screening approaches, with less health care costs, less harms, and a bigger net benefit. In addition, lab methodology should be harmonised.

Correcting uterine cancer mortality in Estonia using linkage of causes of death and cancer registry data, 2000–2021

Cervical and corpus uteri cancer mortality may be underestimated due to a proportion of deaths attributed to unspecified uterine cancer. The aim was to estimate corrected mortality rates and trends for cervical and corpus uteri cancer in Estonia after reallocation of underlying cause of death using individual linkage of death records and cancer registry records. Deaths in Estonian female population in 2000-2021 with the underlying cause of cervical cancer (ICD-10 code C53), corpus uteri cancer (C54) or cancer of uterus not otherwise specified (C55) were individually linked to Estonian Cancer Registry to identify any cancers diagnosed in these persons. Underlying cause of death was reallocated if applicable. Original and corrected age-standardized (world) mortality trends were modelled using joinpoint regression. During 2000-2021, the corrected number of deaths was 1409 cervical cancer deaths (originally 1388, 1.5 % increase), 1146 corpus uteri cancer deaths (902, 27 % increase), and 50 unspecified uterine cancer deaths (368, 86 % decrease). Proportion of unspecified deaths decreased from 26 % (2000-2004) to 4 % (2016-2021) (p < 0.001). After correction, cervical cancer mortality trend steepened slightly from 0.8 % decrease per year to 1.1 % decrease (both significant). Corpus uteri cancer mortality trend changed direction from significant increase of 1.9 % per year to significant decrease of 1.4 % per year. Routine linkage of causes of death records with cancer registry is warranted for validating underlying cause of death. The results emphasize the importance of the availability of medical documentation for physicians assigning cause of death as well as relevant training.

HPV self-sampling in organized cervical cancer screening program: A randomized pilot study in Estonia in 2021

Background Cervical cancer incidence in Estonia ranks among the highest in Europe, but screening attendance has remained low. This randomized study aimed to evaluate the impact of opt-in and opt-out human papillomavirus (HPV) self-sampling options on participation in organized screening. Methods A random sample of 25,591 women were drawn from the cervical cancer screening target population who were due to receive a reminder in autumn 2021 and thereafter randomly allocated to two equally sized intervention arms (opt-out and opt-in) receiving a choice between HPV self-sampling or clinician sampling. In the opt-out arm, a self-sampler was sent to home address by regular mail; the opt-in arm received an e-mail containing a link to order a self-sampler online. The remaining 30,102 women in the control group received a standard reminder for conventional screening. Participation by intervention arm, age and region of residence was calculated; a questionnaire was used to assess self-sampling user experience. Results A significant difference in participation was seen between opt-out (41.7%) (19.8% chose self-sampling and 21.9% clinician sampling), opt-in (34.1%) (7.9% self-sampling, 26.2% clinician sampling) and control group (29.0%, clinician sampling only). All age groups and regions in the intervention arms showed higher participation compared to the control group, but the size of the effect varied. Among self-sampling users, 99% agreed that the device was easy to use and only 3.5% preferred future testing at the clinic. Conclusion Providing women with a choice between self-sampling and clinician sampling significantly increased participation in cervical cancer screening. Opt-in and opt-out options had a different effect across age groups, suggesting the need to adapt strategies.

Human papillomavirus self-sampling for long-term non-attenders in cervical cancer screening: A randomised feasibility study in Estonia

Objective Organised cervical cancer screening was started in Estonia in 2006, but participation is still low. Human papillomavirus (HPV) self-sampling has proved to increase screening uptake. This study addressed the feasibility of HPV self-sampling and the acceptance of this method among long-term screening non-attenders. Methods A randomised intervention study was conducted in Estonia in 2020. Women born in 1958–1983 without a Pap smear in 2013–2019 were identified in the Estonian Health Insurance Fund database. From them, 12,000 women were randomly allocated to three equal-sized study groups. The opt-out group received a questionnaire and a Qvintip® sampling device by regular mail. Two opt-in groups received a questionnaire and an e-mail invitation to order a self-sampler online; one received Qvintip and the other Evalyn® Brush. Participantś background characteristics were obtained from the Population Register. The effect of covariates on participation rate was estimated with multivariate Poisson regression. Acceptance of self-sampling was analysed according to agreement with statements in the questionnaire. Results The overall participation rate was 16% with significant differences between opt-out (26%) and opt-in (11%) groups. Compared to the opt-out Qvintip group, adjusted relative risks for the Qvintip and Evalyn Brush opt-in groups were 0.41 (95% confidence interval (CI) 0.37–0.45) and 0.44 (95% CI 0.40–0.49), respectively. Participation was associated with living place, citizenship, and education. Self-sampling was well accepted: 98% agreed that it was easy to use, 88% preferred it as a screening method in future. Conclusions The results show the feasibility and good acceptance of HPV self-sampling among long-term screening non-attenders in Estonia.