Recent trends in incidence of five common cancers in 26 European countries since 1988: Analysis of the European Cancer Observatory

Abstract

Background

Individual country- and cancer site-specific studies suggest that the age-adjusted incidence of many common cancers has increased in European populations over the past two decades. To quantify the extent of these trends and the recent burden of cancer, here we present a comprehensive overview of trends in population-based incidence of the five common cancers across Europe derived from a new web-based portal of the European cancer registries.

Methods

Data on incidence for cancers of the colon and rectum, prostate, breast, corpus uteri and stomach diagnosed from 1988 to 2008 were obtained from the European Cancer Observatory for cancer registries from 26 countries. Annual age-standardised incidence rates and average annual percentage changes were calculated.

Results

Incidence of four common cancers in eastern and central European countries (prostate, postmenopausal breast, corpus uteri and colorectum) started to approach levels in northern and western Europe, where rates were already high in the past but levelled off in some countries in recent years. Decreases in stomach cancer incidence were seen in all countries.

Discussion

Increasing trends in incidence of the most common cancers, except stomach cancer, are bad news to public health but can largely be explained by well-known changes in society in the past decades. Thus, current and future efforts in primary cancer prevention should not only remain focussed on the further reduction of smoking but engage in the long-term efforts to retain healthy lifestyles, especially avoiding excess weight through balanced diets and regular physical exercise.

Introduction

Cancer has emerged as a leading cause of morbidity and mortality in European populations [1]. This development has made population-based, accurate and near-term information on cancer occurrence extremely valuable in order to identify trends, and risk factors driving those trends. Such data are also the foundation for adequate and purposeful cancer prevention, which needs to be continuously adapted according to the best available scientific evidence and knowledge [2]. Several initiatives at the European level have led to the formation of a network of cancer registries, allowing for comparisons across countries that provide insights into the impact of different risk factors, detection methods and treatment practices on the variation in cancer incidence and survival [3], [74].

Smoking, dietary habits and reproductive factors have been identified as the main (modifiable) risk factors for cancer in populations in industrialised countries, with different magnitudes and implications across countries and regions [4], [5]. Parallels between changes in the prevalence of those risk factors in the past and cancer incidence today highlight and confirm associations known for years. While smoking prevalence is still increasing in women in some countries in southern and central Europe [6], [7], it has decreased in men in Europe since the 1960s, leading to declines in lung cancer incidence since the 1980s or 1990s, first in northern and western Europe and later in eastern and southern Europe [8], [74]. At least 3–6% of all cancers in Europe have been related to high body mass index (BMI) and currently observed increases in BMI across all European countries [9], [10]. Although the impact of these recent changes in risk factor prevalence will only be fully reflected in cancer burden in the next 20–30 years [11], monitoring current trends may enable us to anticipate future increases in cancer burden.

Progress in cancer control has recently been measured using trends in incidence, mortality and survival based on data from 21 European cancer registries [12]. While improvements in early detection as well as treatment options have translated into an ongoing increase in survival and decrease in mortality, cancer prevention efforts have so far yielded only moderate successes. In this study, we aim to describe recent trends in incidence of the most common cancers in Europe in the past two decades, complementing the study of [74] on trends in incidence of smoking-related cancers. Population-based incidence data from cancer registries in 26 countries from the European Cancer Observatory [13] and Cancer Incidence in Five Continents (CI5) [14] were used to assess trends across European regions, age groups and sex. Where possible, incidence trends were assessed in the light of the changing prevalence of several known risk factors in European populations. This approach will shed light on the potential for improvement in cancer prevention.