Breast cancer is the most common cancer in women in the EU

The breast is by far the most common site of cancer in women in the EU (excluding non-melanoma skin cancer). It is also the most common female cancer in the world although incidence and mortality rates vary significantly between countries. This cancer is very rare in men.

In women, the number of new annual cases of breast cancer in Europe is at least twice that of new cancers at any other site (Ferlay et al., 2004). One in 10 women in the EU-27 will develop breast cancer before the age of 80 years (Curado et al., 2007).

Breast cancer incidence rates increase with age, rapidly among pre-menopausal and more slowly among post-menopausal women. This pattern of flattening after menopause is not observed for other tumours, which strongly suggests that reproductive hormones play an important role in the development of breast cancer. In the EU more than 70% of the cases occur after the age of 49 years (Curado et al., 2007).

Incidence has been rising for decades but first signs of stabilisation have been observed

Population-based cancer registries have consistently documented a continuing rise of incidence rates since the 1960s. Incidence is still on the increase but the first slow-downs have been observed since 2002. It has been estimated that there were 319,000 newly diagnosed cases in the EU-25 in 2006 (Ferlay et al., 2007).

Mass screening temporarily led to increased incidence

In the 1990s mass screening by mammography further boosted the increase of registered incidence wherever it was introduced, by enabling earlier and more complete detection of cases. The degree of increase depended on the coverage and intensity of the programmes. The increase itself was temporary. The benefit of screening is that diagnosis in an earlier stage permits a more effective treatment.

The North-South gradient across Europe is diminishing

Before the introduction of mass screening in the 1990s, breast cancer incidence was the highest in Northern Europe, intermediate in Central Europe and the lowest in Southern and Eastern European countries. Estimates for 2006 show that geographical differences have been shrinking, due to rapid increases in incidence rates in the South. See Estimated incidence of breast cancer throughout Europe in 1990 and 2006.

Breast cancer more prevalent in affluent communities

When looking at the worldwide situation, we see that the risk of breast cancer is greater both in the more affluent countries of the world and in higher socio-economic groups within countries (Faggiano et al., 1997). See Estimated incidence of breast cancer throughout the world in 2002.

Possible involvement of hormone replacement therapy

In the US breast cancer incidence fell suddenly in 2003 after having been flat for several years. It was suggested that this could be due to the sudden decline in users of HRT (Ravdin et al., 2007) following the publication of a clinical trial which demonstrated an increase of breast cancer in users of HRT (Rossouw et al., 2002). Women in European countries also discontinued HRT following this publication, but no such dramatic decline has been observed here as yet.

Also see Estimated incidences, survival rates and trend in mortality of breast cancer throughout Europe (interactive - click on Indicators to select desired topic).