Effect of organised screening on cervical cancer incidence and mortality in Finland, 1963-1995: recent increase in cervical cancer incidence.

A nation-wide screening programme for cervical cancer started in Finland gradually from 1963 onwards. By the beginning of the 1990s, there had been a decrease of 80% both in the age-adjusted incidence of and mortality from cervical cancer. To describe the recent patterns in cervical cancer incidence and mortality and evaluate their differentials in relation with the organised screening activities, we have updated the material on the cervical cancer incidence and mortality as well as mass-screening activities up to the year 1995. Based on the files of the Finnish Cancer Registry, there is a striking increase of about 60% in the incidence of cervical cancer during the last 4 years of the study period among women below 55 years of age. The mortality rates are still decreasing. There is no overall decrease over recent years in the coverage of the programme invitations or smears taken. Incidence of invasive cancer and of moderate and severe dysplasia as detected in mass screening have increased. As to the interpretation, changes in the risk factors, such as in sexual behaviour and smoking habits, over the decades might partly explain increasing trends in cervical cancer incidence. As the change in incidence was relatively abrupt, inadequacies or changes in the effectiveness in the screening programme, particularly among young women, may also have contributed. Expanding the coverage of and attendance in the pap-screening programme among women in young target ages would still be effective. Increasing emphasis on quality assessment in screening is also needed. Copyright 1999 Wiley-Liss, Inc.