More than 1 million cases of breast cancer are now diagnosed worldwide each year. The lifetime risk for women is now 1 in 9 (11%), which is predicted to rise to 1 in 7 women by the year 2024, and breast cancer represents 10% of all new cancers and 23% of female cancer cases.
The incidence of breast cancer is increasing year after year in Western populations and highest rates of breast cancer are currently found in more affluent (richer) social classes. The lowest rates are found in rural Africa and Asia where women still have many children, early first pregnancies and breast feed for a long period of time (all three factors lower breast cancer risk). Traditionally lower breast cancer rates have been found in Central/Eastern Europe and the Far East but these are now rising rapidly. In China the increase has been caused by a drop in the birth rate and exposure of Chinese women to lifestyle risk factors that increase breast cancer risk including weight gain, alcohol and hormone replacement therapy.
Breast cancer survival is now increasing in Western populations due to the development of specialist teams (like Cambridge), earlier detection due to greater awareness and breast screening, and better access to treatment following surgery (chemotherapy, radiotherapy, hormone therapy). It is well recognised that women treated by breast cancer specialists live longer1,2 and currently 2 out of 3 women (66%) now live for 20 years following optimal breast cancer treatment. The breast cancer survival in Cambridge UK, and the East of England, is now similar to the best countries in Europe including Norway and Finland.3 Finally there is now much published evidence to show that women with breast cancers detected by screening mammograms live longer as they tend to present with smaller tumours that are less likely to have spread4,5