Effect of screening in the Nordic cancer control up to the year 2017.

The purpose of this study was to estimate the effect of screening for cancer on mortality, quality of life and cost in the Nordic countries up to 2017. Data from the Nordic Cancer Registries were used to predict, by means of the age-period cohort models, cancer mortality assuming no screening, the screening actually practised and most effective screening observed. Cost of screening was assessed assuming the cost of breast, cervical and colorectal cancer screening per person as well as treatment, follow-up and terminal care by stage. The results were adjusted for quality of life directly associated with screening and indirectly induced as dementia by the prolongation of life. Ultimately, in the year 2017 screening will prevent about 4000 deaths in the Nordic countries, most (91%) cervical cancer and a smaller proportion of breast cancer (18%) and colorectal cancer (18%) deaths are preventable. This is equal to 5.7% among all potential cancer deaths in 2017, which corresponds to about one life year gained due to all cancer screening per 1000 years lived by the Nordic population in 2017. Adjustment for quality of life may at most reduce the benefit by about 20%. The cost of screening for breast cancer is expensive, that for cervical cancer is likely to be cost saving, and cost of screening for colorectal cancer may occupy an intermediate position. It is concluded that about 6% of the cancer deaths in the Nordic countries can be prevented by screening. This figure is fully realistic given the Nordic type of organized screening programmes, whereas many other predictions affecting cancer burden are more speculative.