Outcomes of African American (AA) versus caucasian (CA) women with triple-negative (TN) breast cancer following preoperative anthracycline and taxane-based chemotherapy

Abstract

11530 Background: Although AA have a lower incidence of breast cancer compared to CA, they are more likely to present with a TN phenotype and to have a higher mortality rate. Chemotherapy is the only adjuvant treatment available to women with a TN breast cancer phenotype. Data suggest that TN tumors are overall highly sensitive to preoperative chemotherapy but have a worse prognosis when compared to other breast cancer subtypes. We hypothesized that a contributing factor to a worse outcome in AA may be a poor response to anthracycline and taxane based chemotherapy. Methods: We conducted a retrospective review of treatment outcomes of women with TN breast cancer who received preoperative anthracycline and/or taxane-based regimens. We compared pathologic complete response (pCR), a surrogate marker for long-term survival, in AA to CA or other racial groups using Fisher’s exact test and logistic regression model for multivariate analysis. Disease free survival (DFS) and overall survival (OS) were compared using log-rank tests and Cox regression analyses. Results: We identified 39 women who received preoperative therapy for TN breast cancer from May 2002 to January 2007, including 13 AA, 20 CA and 6 from other racial groups (Table). AA women with TN breast cancer had a significantly worse pCR compared to women of other races before and after adjustment for patient heterogeneity. We also observed a trend toward a worse DFS and OS in AA. Conclusions: AA women with TN breast cancers have a significantly worse pCR rate following anthracycline and/or taxane based regimens. A larger sample size is required to evaluate differences in DFS and OS among the racial groups. New treatments are required for women diagnosed with TN breast cancer, especially for AA. Analysis of basal markers and gene methylation in this dataset is underway. Patient Characteristics Characteristic Race (%) P AA (N=13) CA or Other (N=26) Age < 51 85 42 0.017 Clinical Stage 3 69 38 0.035 pCR 31 77 0.014 DFS at 3-year 33 77 0.069 OS at 3- year 42 73 0.047 No significant financial relationships to disclose.