Breast Cancer Research and Treatment

, Volume 145, Issue 3, pp 743–751 | Cite as

Racial disparities in initiation of adjuvant endocrine therapy of early breast cancer

  • Katherine E. Reeder-HayesEmail author
  • Anne Marie Meyer
  • Stacie B. Dusetzina
  • Huan Liu
  • Stephanie B. Wheeler


Endocrine therapy (ET) is the cornerstone of adjuvant therapy for hormone-receptor positive (HR+) breast cancer. The survival gap between African-American (AA) and white women with breast cancer is most pronounced in HR+ subtypes, and could be related to differences in ET use. The relationship between race and initiation of ET is not well defined. We investigated patterns of ET initiation by race in a diverse cohort of women covered by commercial health insurance. We identified 2,640 women with incident HR+ breast cancer in the North Carolina Central Cancer Registry whose records linked to commercial insurance claims using the Integrated Cancer Information and Surveillance System (ICISS) database. The sample included women age <65 years diagnosed with stage I–III HR+ cancers between 2004 and 2009. We used multivariate Poisson regression to examine the effect of race on likelihood of initiating ET. 14 % of women did not initiate ET within 12 months of diagnosis. AA women were 17 % less likely to initiate ET than whites (aRR 0.83, 95 % CI 0.74–0.93). When analyzed by subset, racial disparities persisted among women who received chemotherapy (aHR 0.67, 95 % CI 0.56–0.80) but not among women who did not receive chemotherapy (aHR 0.96, 95 % CI 0.76–1.21). AA women in our sample were less likely to initiate ET than whites, and this disparity was concentrated among chemotherapy-treated women. ET under-utilization may contribute to the racial survival gap in HR+ breast cancer, and represents an opportunity for intervention to reduce breast cancer disparities.


Breast cancer Health care disparities Tamoxifen Aromatase inhibitors Medication adherence 



Dr. Reeder-Hayes and Dr. Dusetzina received funding support from career development awards through the Building Interdisciplinary Careers in Womens’ Health (BIRCWH) program of the National Institutes of Health (5K12HD001441-12) during the conduct of this research. The Integrated Cancer Information and Surveillance Systems (ICISS) is supported in part by the University Cancer Research Fund of the Lineberger Comprehensive Cancer Center, through funds allocated by the General Assembly of the State of North Carolina.

Conflict of interest

The authors have declared that they have no financial conflicts of interest.


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Katherine E. Reeder-Hayes
    • 1
    • 2
    Email author
  • Anne Marie Meyer
    • 1
    • 4
  • Stacie B. Dusetzina
    • 3
    • 4
  • Huan Liu
    • 1
  • Stephanie B. Wheeler
    • 1
    • 5
  1. 1.University of North Carolina Lineberger Comprehensive Cancer CenterChapel HillUSA
  2. 2.Division of Hematology/OncologyUniversity of North Carolina School of MedicineChapel HillUSA
  3. 3.Division of General MedicineUniversity of North Carolina School of MedicineChapel HillUSA
  4. 4.Department of EpidemiologyGillings School of Global Public HealthChapel HillUSA
  5. 5.Department of Health Policy and ManagementGillings School of Global Public Health University of North CarolinaChapel HillUSA

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