Largest ever study on European cancer prevalence shows large differences between countries

Prioritise resources towards primary prevention, say EUROPREVAL researchers

The largest study on the prevalence of cancer in Europe is published today (Thursday 6 June) in Annals of Oncology, journal of the European Society for Medical Oncology.

Thirty-eight cancer registries in 17 countries provided data on 3 million cancer patients for EUROPREVAL. An objective of the study was to provide health systems with essential information for health planning and resource allocation.

Cancer prevalence is the number of patients with the disease in the population at a given time. This is not the same as incidence, which is the number of new cases of cancer arising in a given period in a specified population.

The international team of researchers found large differences between countries for overall prevalence of cancer, with estimates ranging from a low of 1,170 per 100,000 in the Polish cancer registration areas to a high of 3,050 per 100,000 in southern Sweden. For most cancers, the Swedish, Swiss, German and Italian registries had high prevalence and the Polish, Estonian, Slovakian and Slovenian areas had low prevalence. But there were also wide variations between countries for individual cancers.

Of the total prevalent cases 61% were women, with all countries showing higher prevalence among women. Breast cancer accounted for 34% of the female cancers. The most prevalent cancer among men Europe-wide was colorectal cancer, accounting for 15% of all male prevalent cancers. People of 65 and over accounted for 57%. Prevalence tended to be high where incidence was high, but was also highest in countries where survival was high.

The research team found that high prevalence was associated with low general and infant mortality and with high gross domestic product and high total health expenditure, suggesting that cancer prevalence will rise as the level of economic development rises. The report states that cancer prevalence is therefore both an indicator of positive and negative aspects of economic development – increasing life expectancy and survival from cancer on the one hand, but increasing incidence on the other.

According to the researchers this in turn suggested that although notable results have been achieved, the campaign against cancer in Europe has not concentrated sufficient energy or resources on primary prevention.

They concluded that the expected increases in prevalence with economic development will therefore require more resources and that primary prevention should receive priority.

However, the EUROPREVAL figures relate to cancer patients diagnosed from 1970 to 1992, 22% of whom consisted of people who had been diagnosed within two years of the index date, and an accompanying editorial queries how useful these figures will be to planners.

Professor Graham Giles warned that sources of possible error relating to the quality of cancer registries provided “a cautionary tale” for using the data for international comparisons or for health service planning. “Prevalence estimates are susceptible to the forces that drive the incidence of, and survival from, specific cancer types, particularly with respect to those cancers that are not uniformly and rapidly fatal,” said Professor Giles, who is from the Cancer Epidemiology Centre, Anti-Cancer Council of Victoria in Australia.

“Total prevalence based on a complete estimation of survivors of all cancer types has a rather limited application. Many long-term survivors will, essentially, be cured of their cancer and may place little additional burden the health services than others of their age,” he concluded.

A second paper , which examined the methods used to calculate prevalence, reviewed the problems encountered and how they could be overcome. The authors concluded that work in progress to break down total prevalence by disease stage would provide more informative indicators for planning the allocation of health resources.