Breast cancer control: signs of progress, but more work required.

Breast cancer represents 10% of the global cancer burden and there is no population, or population sub-group, which has yet been identified to be at a truly low risk of developing the disease. Mortality rates have been steadily growing for nearly a century in many countries and it is only during the past decade that there have been signs of a sustainable decrease in mortality rates in a number of western-lifestyle countries. This represents considerable progress in breast cancer control and, although different factors contribute to different degrees in different countries, is mainly due to increased breast awareness, earlier detection and the delivery of the most appropriate therapy to women with the disease. The failure to prevent the incidence from continuing to rise represents to a great extent the failure to understand the precise mechanisms of breast carcinogenesis and the role of risk determinants whose alteration in society could lead to a reduced risk of developing the disease. The declines seen in mortality represent a considerable success, but there is no room for complacency until research can impact positively on reducing incidence.