Summary Background Cervical cancer incidence remains high in several Baltic, central, and eastern European (BCEE) countries, mainly as a result of a historical absence of effective screening ...programmes. As a catalyst for action, we aimed to estimate the number of women who could be spared from cervical cancer across six countries in the region during the next 25 years, if effective screening interventions were introduced. Methods In this population-based study, we applied age–period–cohort models with spline functions within a Bayesian framework to incidence data from six BCEE countries (Estonia, Latvia, Lithuania, Belarus, Bulgaria, and Russia) to develop projections of the future number of new cases of cervical cancer from 2017 to 2040 based on two future scenarios: continued absence of screening (scenario A) versus the introduction of effective screening from 2017 onwards (scenario B). The timespan of available data varied from 16 years in Bulgaria to 40 years in Estonia. Projected rates up to 2040 were obtained in scenario A by extrapolating cohort-specific trends, a marker of changing risk of human papillomavirus (HPV) infection, assuming a continued absence of effective screening in future years. Scenario B added the effect of gradual introduction of screening in each country, under the assumption period effects would be equivalent to the decreasing trend by calendar year seen in Denmark (our comparator country) since the progressive regional introduction of screening from the late 1960s. Findings According to scenario A, projected incidence rates will continue to increase substantially in many BCEE countries. Very high age-standardised rates of cervical cancer are predicted in Lithuania, Latvia, Belarus, and Estonia (up to 88 cases per 100 000). According to scenario B, the beneficial effects of effective screening will increase progressively over time, leading to a 50–60% reduction of the projected incidence rates by around 2040, resulting in the prevention of cervical cancer in 1500 women in Estonia and more than 150 000 women in Russia. The immediate launch of effective screening programmes could prevent almost 180 000 new cervical cancer diagnoses in a 25-year period in the six BCEE countries studied. Interpretation Based on our findings, there is a clear need to begin cervical screening in these six countries as soon as possible to reduce the high and increasing incidence of cervical cancer over the next decades. Funding None.
Summary Background Intrauterine device (IUD) use has been shown to reduce the risk of endometrial cancer, but little is known about its association with cervical cancer risk. We assessed whether IUD ...use affects cervical human papillomavirus (HPV) infection and the risk of developing cervical cancer. Methods We did a pooled analysis of individual data from two large studies by the International Agency for Research on Cancer and Institut Català d'Oncologia research programme on HPV and cervical cancer; one study included data from ten case–control studies of cervical cancer done in eight countries, and the other included data from 16 HPV prevalence surveys of women from the general population in 14 countries. 2205 women with cervical cancer and 2214 matched control women without cervical cancer were included from the case–control studies, and 15 272 healthy women from the HPV surveys. Information on IUD use was obtained by personal interview. HPV DNA was tested by PCR-based assays. Odds ratios and 95% CIs were estimated using multivariate unconditional logistic regression for the associations between IUD use, cervical HPV DNA, and cervical cancer. Findings After adjusting for relevant covariates, including cervical HPV DNA and number of previous Papanicolaou smears, a strong inverse association was found between ever use of IUDs and cervical cancer (odds ratio 0·55, 95% CI 0·42–0·70; p<0·0001). A protective association was noted for squamous-cell carcinoma (0·56, 0·43–0·72; p<0·0001), adenocarcinoma and adenosquamous carcinoma (0·46, 0·22–0·97; p=0·035), but not among HPV-positive women (0·68, 0·44–1·06; p=0·11). No association was found between IUD use and detection of cervical HPV DNA among women without cervical cancer. Interpretation Our data suggest that IUD use might act as a protective cofactor in cervical carcinogenesis. Cellular immunity triggered by the device might be one of several mechanisms that could explain our findings. Funding Instituto de Salud Carlos III; Agència de Gestió d'Ajuts Universitaris i Recerca; Marató TV3 Foundation; Bill & Melinda Gates Foundation; International Agency for Research on Cancer; European Community; Fondo de Investigaciones Sanitarias, Spain; Preventiefonds, Netherlands; Programa Interministerial de Investigación y Desarrollo, Spain; Conselho Nacional de Desenvolvimiento Cientifico e Tecnologico, Brazil; and Department of Reproductive Health & Research, WHO.
PDF
