Background: Information on cancer prevalence is of major importance for health planning and resource allocation. However, systematic information on cancer prevalence is largely unavailable, Materials and methods: Thirty-eight population-based cancer registries from 17 European countries, participating in EUROPREVAL, provided data on almost 3 million cancer patients diagnosed from 1970 to 1992. Standardised data collection and validation procedures were used and the whole data set was analysed using proven methodology. The prevalence of stomach, colon, rectum, lung, breast, cervix uteri, corpus uteri and prostate cancer, as well as of melanoma of skin, Hodgkin's disease, leukaemia and all malignant neoplasms combined, were estimated for the end of 1992. Results: There were large differences between countries in the prevalence of all cancers combined; estimates ranged from 1170 per 100000 in the Polish cancer registration areas to 3050 per 100000 in southern Sweden. For most cancers, the Swedish, Swiss, German and Italian areas had high prevalence, and the Polish, Estonian, Slovakian and Slovenian areas had low prevalence. Of the total prevalent cases, 61% were women and 57% were 65 years of age or older. Cases diagnosed within 2 years of the reference date formed 22% of all prevalent cases. Breast cancer accounted for 34% of all prevalent cancers in females and colorectal cancer for 15% in males. Prevalence tended to be high where cancer incidence was high, but the prevalence was highest in countries where survival was also high. Prevalence was low where general mortality was high (correlation between general mortality and the prevalence of all cancers = -0.64) and high where gross domestic product was high (correlation = +0.79) Thus, the richer areas of Europe had higher prevalence, suggesting that prevalence will increase with economic development. Conclusions: EUROPREVAL is the largest project on prevalence conducted to date. It has provided complete and accurate estimates of cancer prevalence in Europe, constituting essential information for cancer management. The expected increases in prevalence with economic development will require more resources; allocation to primary prevention should therefore be prioritised.
