Early-stage breast cancer adjuvant therapy and survival have changed over the last 20 years. Using the National Cancer Institute’s population-based patterns of care studies, we examined adjuvant multi-agent chemotherapy and endocrine therapy utilization and cancer survival among women diagnosed with early-stage, invasive breast cancer in 1990, 1995, 2000, 2005, and 2010 who were sampled from Surveillance, Epidemiology and End Results (SEER) registries. Medical records were re-abstracted and treatment verified with physicians. Logistic regression and Cox proportional hazards regression were utilized to identify factors associated with treatment and 3-yr cancer survival. Utilization of multi-agent chemotherapy increased, regardless of nodal and estrogen receptor (ER) status but most notably among women with ER-positive tumors. There were significant changes in preferred chemotherapy regimen overtime: from cyclophosphamide, methotrexate and 5-fluorouracil (CMF) in 1990 to anthracycline, cyclophosphamide and taxane (AC-T) in 2000 to cyclophosphamide and taxane (TC) in 2010. Endocrine therapy decreased among women with ER-negative tumors and increased among women with node-negative, ER-positive tumors. Utilization of aromatase inhibitors rapidly increased. More recent diagnosis year and younger age were consistently associated with receipt of adjuvant therapy. Poorer survival was associated with earlier diagnosis year, older age, being non-Hispanic black, having more extensive disease and not receiving endocrine therapy. In conclusion, adjuvant therapy utilization and 3-year cancer survival increased over time. Whether the expanded use of genomic testing and personalize medicine influences the national trends in adjuvant therapy and survival remains to be seen.
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