Racial disparities in initiation of adjuvant endocrine therapy of early breast cancer
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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.
KeywordsBreast 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.
- 1.Bach PB, Guadagnoli E, Schrag D, Schussler N, Warren JL (2002) Patient demographic and socioeconomic characteristics in the SEER-Medicare database applications and limitations. Med Care 40 (8 Suppl):IV-19-25. doi: 10.1097/01.MLR.0000020934.40692.C0
- 2.Edwards BK, Brown ML, Wingo PA, Howe HL, Ward E, Ries LA, Schrag D, Jamison PM, Jemal A, Wu XC, Friedman C, Harlan L, Warren J, Anderson RN, Pickle LW (2005) Annual report to the nation on the status of cancer, 1975–2002, featuring population-based trends in cancer treatment. J Natl Cancer Inst 97(19):1407–1427. doi: 10.1093/jnci/dji289 PubMedCrossRefGoogle Scholar
- 3.O’Brien KM, Cole SR, Tse CK, Perou CM, Carey LA, Foulkes WD, Dressler LG, Geradts J, Millikan RC (2010) Intrinsic breast tumor subtypes, race, and long-term survival in the carolina breast cancer study. Clin Cancer Res 16(24):6100–6110. doi: 10.1158/1078-0432.CCR-10-1533 PubMedCentralPubMedCrossRefGoogle Scholar
- 7.Friese CR, Pini TM, Li Y, Abrahamse PH, Graff JJ, Hamilton AS, Jagsi R, Janz NK, Hawley ST, Katz SJ, Griggs JJ (2013) Adjuvant endocrine therapy initiation and persistence in a diverse sample of patients with breast cancer. Breast Cancer Res Treat 138(3):931–939. doi: 10.1007/s10549-013-2499-9 PubMedCentralPubMedCrossRefGoogle Scholar
- 9.Owusu C, Buist DS, Field TS, Lash TL, Thwin SS, Geiger AM, Quinn VP, Frost F, Prout M, Yood MU, Wei F, Silliman RA (2008) Predictors of tamoxifen discontinuation among older women with estrogen receptor-positive breast cancer. J Clin Oncol 26(4):549–555. doi: 10.1200/JCO.2006.10.1022 PubMedCrossRefGoogle Scholar
- 11.Hershman DL, Kushi LH, Shao T, Buono D, Kershenbaum A, Tsai WY, Fehrenbacher L, Lin Gomez S, Miles S, Neugut AI (2010) Early discontinuation and nonadherence to adjuvant hormonal therapy in a cohort of 8,769 early-stage breast cancer patients. J Clin Oncol 28(27):4120–4128. doi: 10.1200/JCO.2009.25.9655 PubMedCentralPubMedCrossRefGoogle Scholar
- 12.Hershman DL, Shao T, Kushi LH, Buono D, Tsai WY, Fehrenbacher L, Kwan M, Gomez SL, Neugut AI (2011) Early discontinuation and non-adherence to adjuvant hormonal therapy are associated with increased mortality in women with breast cancer. Breast Cancer Res Treat 126(2):529–537. doi: 10.1007/s10549-010-1132-4 PubMedCentralPubMedCrossRefGoogle Scholar
- 15.Livaudais JC, Hershman DL, Habel L, Kushi L, Gomez SL, Li CI, Neugut AI, Fehrenbacher L, Thompson B, Coronado GD (2012) Racial/ethnic differences in initiation of adjuvant hormonal therapy among women with hormone receptor-positive breast cancer. Breast Cancer Res Treat 131(2):607–617. doi: 10.1007/s10549-011-1762-1 PubMedCentralPubMedCrossRefGoogle Scholar
- 17.Short LJ, Fisher MD, Wahl PM, Kelly MB, Lawless GD, White S, Rodriguez NA, Willey VJ, Brawley OW (2010) Disparities in medical care among commercially insured patients with newly diagnosed breast cancer: opportunities for intervention. Cancer 116(1):193–202. doi: 10.1002/cncr.24691 PubMedGoogle Scholar
- 18.Livaudais JC, Lacroix A, Chlebowski RT, Li CI, Habel LA, Simon MS, Thompson B, Erwin DO, Hubbell FA, Coronado GD (2013) Racial/ethnic differences in use and duration of adjuvant hormonal therapy for breast cancer in the women’s health initiative. Cancer Epidemiol Biomark Prev 22(3):365–373. doi: 10.1158/1055-9965.EPI-12-1225 CrossRefGoogle Scholar