Prevention strategies for breast cancer

In the last decade there has been a steady increase in the incidence of breast cancer in the Western world. The increase in early diagnosis and improvements in treatment modalities have helped to reduce the mortality rate. A major impact on the incidence and mortality from breast cancer, however, can be expected only if we learn to modulate the process of carcinogenesis at the preclinical levels. This modulation or chemoprevention, requires a combined and well-defined strategic approach that ideally include 1) a clear description and quantification of the specific risk factors (environmental, hormonal, genetic and histologic) that may be used in selecting cohorts of women at increased risk for breast cancer; 2) a description of the specific intervention (e.g. chemoprevention, surgery or both) that are required for the specific risk factor identified; 3) the identification and preclinical evaluation of cancer chemopreventive agents and the subsequent development of definitive, large-scale clinical trials; and 4) the identification and characterization of specific molecular biomarkers that may be quantitatively assessed and used as surrogate endpoint-biomarkers (SEBs) in future trials. In this review we consider these guidelines, focusing, on a description of recognized and risk factors for invasive breast cancer. We also discuss the recent achievements in and the outlook for chemoprevention in breast cancer.