Variations in breast cancer treatment by patient and provider characteristics.

Guidelines for the optimal treatment of breast cancer have been publicized over the past 15 years, yet clinical practices continue to vary substantially in the United States. This article reviews the literature on variations in local and systemic treatment of breast cancer by patient and provider characteristics. Studies of local therapy have consistently demonstrated that older women are less likely than younger women to receive radiation therapy after breast-conserving surgery. Some studies have noted that black women are less likely than white women to receive breast-conserving surgery and less likely to receive radiation therapy after breast-conserving surgery. Rates of breast-conserving surgery vary three-fold among geographic regions and between teaching and non-teaching hospitals. Patients at smaller hospitals appear less likely to receive indicated radiation therapy. Patterns of systemic therapy have not been well described. Women over age 75 may not be receiving adequate hormonal therapy, but recent data are not available. Limited data suggest that rates of systemic therapy do not vary substantially by race or Hispanic ethnicity, but women without health insurance may not be receiving appropriate chemotherapy. Studies relating hospital and physician characteristics to the use of systemic therapy are sparse and inconclusive. In order to increase the proportion of women who receive optimal treatment for breast cancer and ensure greater equity, a more sophisticated understanding of variations in clinical practice will be required. These variations may arise from insufficient knowledge of or disagreement with guidelines among physicians, inadequate communication between physicians and patients, and individual preferences or clinical attributes of patients. Future studies will need to explore the dialogue between women and their physicians that leads to decisions about treatment of breast cancer.