Breast cancer adjuvant chemotherapy decisions in older women: the role of patient preference and interactions with physicians.

PURPOSE: Breast cancer chemotherapy decisions in patients > or = 65 years old (older) are complex because of comorbidity, toxicity, and limited data on patient preference. We examined relationships between preferences and chemotherapy use.
METHODS: Older women (n = 934) diagnosed with invasive (> or = 1 cm), nonmetastatic breast cancer from 2004 to 2008 were recruited from 53 cooperative group sites. Data were collected from patient interviews (87% complete), physician survey (93% complete), and charts. Logistic regression and multiple imputation methods were used to assess associations between chemotherapy and independent variables. Chemotherapy use was also evaluated according to the following two groups: indicated (estrogen receptor [ER] negative and/or node positive) and possibly indicated (ER positive and node negative).
RESULTS: Mean patient age was 73 years (range, 65 to 100 years). Unadjusted chemotherapy rates were 69% in the indicated group and 16% in the possibly indicated group. Women who would choose chemotherapy for an increase in survival of < or = 12 months had 3.9 times (95% CI, 2.4 to 6.3 times; P < .001) higher odds of receiving chemotherapy than women with lower preferences, controlling for covariates. Stronger preferences were seen when chemotherapy could be indicated (odds ratio [OR] = 7.7; 95% CI, 3.8 to 16; P < .001) than when treatment might be possibly indicated (OR = 1.9; 95% CI, 1.0 to 3.8; P = .06). Higher patient rating of provider communication was also related to chemotherapy use in the possibly indicated group (OR = 1.9 per 5-point increase in communication score; 95% CI, 1.4 to 2.8; P < .001) but not in the indicated group (P = .15).
CONCLUSION: Older women's preferences and communication with providers are important correlates of chemotherapy use, especially when benefits are more equivocal.