Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2023 Apr;198(2):187-195.
doi: 10.1007/s10549-022-06826-7. Epub 2023 Jan 23.

Use of endocrine therapy for estrogen receptor-positive breast cancer among American Indians and Alaska natives

Marta Engelking  1 , Schelomo Marmor  2   3 , Mohamad Burjak  2 , Madeleine Hinojos  2 , Whitney Lloyd  2 , Kayla M Switalla  2 , Todd M Tuttle  2
Affiliations
Review

Use of endocrine therapy for estrogen receptor-positive breast cancer among American Indians and Alaska natives

Marta Engelking et al. Breast Cancer Res Treat. 2023 Apr.

Abstract

Background: American Indian/Alaska Native (AI/AN) women with estrogen receptor-positive (ER +) breast cancer have higher mortality compared to non-Hispanic whites (NHW). The purpose of this study is to compare rates of initiation of endocrine therapy (ET) between AI/AN and NHW and further determine survival outcomes for ER + breast cancer.

Methods: We used the National Cancer Database to identify patients diagnosed with ER + breast cancer, stage I-III, between 2004 and 2017. Multivariable logistic regression was performed to determine factors associated with initiation of adjuvant ET. Overall survival was estimated using the Kaplan-Meier analysis and Cox proportional hazards modeling.

Results: We identified a total of 771,619 patients (AI/AN, n = 2473; NHW, n = 769,146). Compared to NHW, AI/AN patients were more likely to live in rural areas, be younger, and have tumors that were higher grade, node positive, and larger. Initiation of adjuvant ET was high in both groups and not significantly different between AI/AN and NHW. Independent predictors of ET initiation included rural location, age, higher tumor grade, node-positive disease, larger tumor size, and progesterone receptor-positive status. Initiation of ET was significantly associated with improved overall survival among all patients. Overall survival was significantly worse among the AI/AN population.

Conclusion: AI/AN race was significantly and independently associated with worse overall survival after diagnosis of ER + breast cancer. We did not find a significant difference in the initiation of adjuvant ET between AI/AN and NHW. Exact reasons why AI/AN women with ER + breast cancer have higher mortality rates remain elusive but are probably multifactorial.

Keywords: Alaska native; American Indian; Breast cancer; Endocrine therapy; Health disparities.

PubMed Disclaimer

References

    1. Global Burden of Disease Cancer Collaboration (2019) Global, regional, and national cancer incidence, mortality, years of life lost, years lives with disability, and disability-adjusted life-years for 29 cancer groups, 1990–2017: a systemic analysis for the global burden of disease study. JAMA Oncol. https://doi.org/10.1001/jamaoncol.2019.2996 - DOI - PMC
    1. Ooi SL, Martinez ME, Li C (2011) Disparities in breast cancer characteristics and outcomes by race/ethnicity. Breast Cancer Res Treat 127(3):729–738. https://doi.org/10.1007/s10549-010-1191-6 - DOI - PubMed
    1. Javid SH, Varghese TK, Morris AM et al (2014) Guideline-concordant cancer care and survival among American Indian/Alaska native patients. Cancer 120(14):2183–2190. https://doi.org/10.1002/cncr.28683 - DOI - PubMed
    1. Wilson RT, Adams-Cameron M, Berhansstipanov L et al (2007) Disparities in breast cancer treatment among American Indian, hispanic and non-hispanic white women enrolled in medicare. J Health Care Poor Underserved 18(3):648–664. https://doi.org/10.1353/hpu.2007.0071 - DOI - PubMed
    1. Early Breast Cancer Trialists’ Collaberative Group (EBCTCG) (2011) Relevance of breast cancer hormone receptors and other factors to the efficacy of adjuvant tamoxifen: patient-level meta-analysis of randomized trials. Lancet 378(9793):771–784. https://doi.org/10.1016/S0140-6736(11)60993-8 - DOI

Substances

LinkOut - more resources