Breast cancer risk: a review of definitions and assessments of risk.

The histopathological and biochemical characteristics of cells and multicellular structure of benign and malignant breast changes have highly significant implications as to the risk of acquiring and dying of breast cancer. Consequently, every breast biopsy merits highly specific histopathological characterization as well as assay for hormone receptors. Certain aspects of a woman's personal and family history may be associated with increased or decreased risk. Clinical application of these variables to the prediction of future outcome requires an understanding of the definitions of risk. These definitions must then be applied appropriately when assessing risk. The definition of risk used must be explicitly stated and consistently used. Provided is a review of the definitions of risk and the risk of acquiring breast cancer according to age, family history, and histopathological characteristics of benign breast biopsies. The highly variable relative risk of dying from breast cancer when diagnosed is also reviewed.