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We provide, to our knowledge, the first evidence of a strong correlation between CTC results and radiographic disease progression in patients receiving chemotherapy or endocrine therapy for MBC. These findings support the role of CTC enumeration as an adjunct to standard methods of monitoring disease status in MBC.

PCPs and oncologists have different preferences for models of cancer survivorship care. Prior involvement with cancer surveillance was one of the strongest predictors of PCPs' willingness to assume this responsibility.

A B S T R A C T PurposeBreast cancer chemotherapy decisions in patients Ն 65 years old (older) are complex because of comorbidity, toxicity, and limited data on patient preference. We examined relationships between preferences and chemotherapy use. MethodsOlder women (n ϭ 934) diagnosed with invasive (Ն 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). ResultsMean 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 Յ 12 months had 3.9 times (95% CI, 2.4 to 6.3 times; P Ͻ .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] ϭ 7.7; 95% CI, 3.8 to 16; P Ͻ .001) than when treatment might be possibly indicated (OR ϭ 1.9; 95% CI, 1.0 to 3.8; P ϭ .06). Higher patient rating of provider communication was also related to chemotherapy use in the possibly indicated group (OR ϭ 1.9 per 5-point increase in communication score; 95% CI, 1.4 to 2.8; P Ͻ .001) but not in the indicated group (P ϭ .15). ConclusionOlder women's preferences and communication with providers are important correlates of chemotherapy use, especially when benefits are more equivocal.