General

The WCRF/AICR report (2007) estimates that in 2002 over 10 million new cases of cancer were diagnosed worldwide, and about 7 million people actually died from cancer. Moreover, these figures are expected to rise to 16 million new cases and 10 million deaths by the year 2020.

In the EU-25, there were over two million (ca 2,29 million) incident cases of cancer in 2006 and over one million cancer deaths (ca 1,17 million) (Ferlay et al., 2007). This represented about 25% of all deaths, making cancer the second cause of death in the EU, after cardiovascular diseases. Further, there is some difference between the sexes, the number of male cancer deaths comprising 56% and that of females 44% of the total of cancer deaths.

Current trends indicate a slow overall decline in cancer deaths in the EU for both males and females. This in contrast to the still increasing incidence of some cancers in the EU, like cancer of the prostate, colon, stomach, oesophagus, and lung (females). As a result of current trends and aging populations, the number of cancer deaths in the EU-25 is estimated to 1,25 million in 2015 (Ferlay et al., 2007).

Causes of cancer

About 5-10% of cancers are the direct result from an inherited defective gene (heritable or familial cancer types). Such cancers occur relatively early in life. The vast majority of cancers however, are due to an accumulation of genetic changes in somatic cells during lifetime, which explains their relatively long latency time. The cause of these genetic changes can be both endogenous (internal) and exogenous (environmental).

From the environmental causes, smoking (and other tobacco use) is the most predominant one. It is estimated to be responsible for 85% of lung cancers and 25% of pancreas cancer. But it is also believed to play a role in cancer of the kidney, oesophagus, mouth, larynx, nasopharynx, and pharynx. In total it may be causally related to some 30% of all cancer cases and deaths.

With regard to food, nutrition, overweight and physical activity, it is much more difficult to indicate their relative contributions to the overall cancer burden. In the early 1980’s epidemiologists have estimated that for nutrition (food and drinks) this might be in the order of 35% too. However, the uncertainties in such estimates were great, resulting in a variation from 10-70%.

As new data became available the original estimates have been refined. It is now generally believed that dietary factors account for around 30% of cancers in industrialized countries, and 20% in developing countries. This figure is an overall figure and clearly varies for different cancer sites. Excess body weight and physical inactivity are estimated to account for between 20% and 33% of cancers of the breast (postmenopausal), colon, endometrium, kidney, and esophagus (Global Cancer Atlas).

Differences in cancer deaths within the EU

In a few countries the percentage of all deaths due to cancer seem notably lower than the average 25%. This holds in particular for the Baltic states, and some east-European countries. In these countries, however, the relative contribution by cardiovascular diseases and external causes appears to be much greater.

Cancer patterns are similar throughout the EU

In almost all EU countries the cancer pattern reflects that of the developed countries, with lung, colon/rectum, breast, prostate, stomach, pancreas, bladder and white blood cells as the most predominant sites. With the exception of stomach cancer, all these sites show generally a higher incidence in developed countries than in developing countries.

In 2006 in Europe, the three most common form of cancers were breast cancer (429,900 new cases: 13.5% of all new cancer cases), colorectal cancers (412,900: 12.9%) and lung cancer (386,300: 12.1%). Lung cancer, with an estimated 334,800 deaths (19.7% of total), was the most common cause of death from cancer, followed by colorectal (207,400 deaths), breast (131,900) and stomach (118,200) cancers (Ferlay et al., 2007).

There are differences between EU-countries with regard to the ranking of the sites. In terms of cancer deaths (both sexes combined), lung cancer and colorectal cancer are clearly number one and two. Lung cancer however, is more frequent in the new member states (East Europe, Baltic), while there is no clear gradient observed (north-south, or east-west) for colorectal cancer.

For the remaining sites the ranking order shows differences per country, i.e. breast and prostate cancer are not always the third or fourth most common cancer site in terms of cancer deaths. For instance, stomach cancer kills more people in the Baltic and some Balkan states, and is also the third most common cancer in Poland, Spain and Portugal. Prostate cancer is the third most common cancer site in Sweden, and also more frequent in Finland and Baltic states. Breast cancer, however, is relatively more frequent in Denmark, Belgium and the Netherlands.