Abstract B53: Racial variation in the uptake of a 21-tumor gene assay in the Carolina Breast Cancer Study cohort

Background: In 2004, a 21-gene assay became commercially available with the potential to aid adjuvant chemotherapy treatment decision-making for women with early stage, hormone receptor positive breast cancer. This assay predicts not only risk of recurrence, but also benefit of adjuvant chemotherapy. With its incorporation into clinical practice guidelines in 2007, this assay may reduce overuse of adjuvant chemotherapy for eligible women and improve the quality of care for women with breast cancer. We examine whether racial differences in the use of the 21-gene assay exists among a large, representative sample of women with breast cancer who receive care in diverse health care settings.

Methods: Data come from Phase III of the Carolina Breast Cancer Study (CBCS-III), a unique and rich dataset that includes survey and medical record abstraction data for 3000 women (1500 white, 1500 black) across North Carolina with invasive breast cancer diagnoses between 2008 and 2013. We will build logistic regression models to examine the impact of race on the use of this assay among women ages 20-74 with early-stage, hormone receptor positive, invasive breast cancer. We will control for patient-level tumor, treatment, and demographic characteristics.

Results: We will present preliminary results regarding racial variation in the uptake of this assay. Furthermore, we will compare the characteristics of women who use the assay with the characteristics of those who do not.

Conclusions: As genomic technologies shift cancer treatment towards personalized therapies, it is critical to understand utilization patterns across racial subgroups. This study will examine whether racial differences exist in the use of a 21-gene assay. Ultimately, these data will be important to understand how genomic technologies may influence racial disparities in cancer processes and outcomes.

Citation Format: Megan C. Roberts, Stephanie B. Wheeler, Katie Reeder-Hayes, Stacie B. Dusetzina, Michaela Dinan, Morris Weinberger. Racial variation in the uptake of a 21-tumor gene assay in the Carolina Breast Cancer Study cohort. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr B53.