Patient preference as a determinant of breast cancer adjuvant chemotherapy use in older women: CALGB #369901

Abstract

9544 Background: Decisions about use of breast cancer chemotherapy in women 65 and older (“older”) can be complex due to comorbidity, uncertain efficacy and limited data on patient preference. Methods: Older women diagnosed with invasive, non-metastatic breast cancer between 2004 and 2008 were recruited from 53 CALGB sites for an observational study of preferences and chemotherapy use. Data on preferences and other factors were collected from patient interviews and clinical data were abstracted from charts. Generalized estimating equation regression was used to assess associations between chart-reported chemotherapy and independent variables; associations were also evaluated in 2 subgroups: “chemotherapy indicated” (estrogen receptor [ER] negative and/or node positive) and “consider chemotherapy” (ER positive and node negative). Results: Among 935 eligible women registered, 815 (87.2%) completed interviews. The mean age of the cohort was 73 years (range 65–100); 38% were node positive, 82% were ER positive and all had tumors ≥ 1 cm (44% were AJCC stage 1, 44% stage 2 and 12% stage 3). Based on ER and nodal status, chemotherapy was “indicated” for 47% and could be “considered” for 53%. Crude chemotherapy rates were 70% in the “indicated” group and 17% in the “considered” group, for an overall rate of 42%. Women who would choose chemotherapy for an increase in survival of ≤12 months were 4.1 times (95% CI 2.5–6.7, p<.0001) more likely to receive chemotherapy than women who would only choose chemotherapy if it added more than 12 months, controlling for age, tumor factors, comorbidity and other covariates. Stronger preferences were seen among women with “indications” for chemotherapy (OR 7.9, 95% CI 3.7–17.0, p<.001) than in those where treatment might be “considered” (OR 1.8, 95% CI 0.9–3.4, p=.08). Higher patient rating of communication with providers was independently related to a decision to use chemotherapy among women where chemotherapy could be “considered” but not among those where chemotherapy was “indicated”. Conclusions: Beyond clinical indications, older women's preferences and communication with providers are important correlates of chemotherapy use. [Table: see text]