Age-related patterns of care: evidence against ageism in the treatment of early-stage breast cancer.

PURPOSE To assess whether the use of adjuvant systemic therapy in postmenopausal women with early-stage breast cancer is influenced by patient age. METHODS A retrospective cohort study based on data collected from medical records and from patients and their surgeons was performed among 746 postmenopausal patients diagnosed with early-stage breast cancer at 30 hospitals located throughout Minnesota. The adjusted odds of receiving hormonal therapy, chemotherapy, and both hormonal therapy and chemotherapy as a function of age was determined. RESULTS Among women with negative lymph nodes, 62% received some form of adjuvant drug therapy. For these women, the likelihood of receiving hormonal therapy or both hormonal therapy and chemotherapy did not vary with patient age and the likelihood of receiving chemotherapy declined with age. Among women with positive lymph nodes, 92% received some form of adjuvant therapy. For these women, the likelihood of receiving hormonal therapy increased with age and the likelihood of receiving chemotherapy declined with age, as did the likelihood of receiving both hormonal therapy and chemotherapy. CONCLUSION The observed associations between age and the use of adjuvant systemic therapy appear to reflect, in general, available information about treatment efficacy and do not suggest underuse among elderly women with early-stage breast cancer. The use of adjuvant therapy depends on clinical factors that predict the increased risk of metastases or the increased likelihood of response to treatment, rather than other sociodemographic factors. Our results also suggest that younger postmenopausal women with positive lymph nodes compared with older women may be undertreated with respect to tamoxifen because of the substitution of chemotherapy for hormonal therapy.