[Evolving strategies over time for treatment of breast cancer].

The natural history of breast diseases has changed overtime and successive therapeutic strategies have been adapted accordingly. Recently, biological findings on geno- and phenotypic characteristics of tumor cells offer new basis for the development of treatments that target homogenous and various subtypes of breast cancer. Unfortunately, traditional clinical research tools are not in phase with rapid changes in both biological knowledge of the disease and new targeted agents. New methodological approaches are urgently needed to validate such changes and improvements in prognosis.