UMMS Affiliation

Division of Epidemiology, Department of Population and Quantitative Health Sciences

Publication Date


Document Type



Clinical Epidemiology | Epidemiology | Health Information Technology | Hormones, Hormone Substitutes, and Hormone Antagonists | Neoplasms | Oncology | Women's Health


Background: Variations in treatment choice, or late stage at first diagnosis, mean that, despite guideline recommendations, not all patients with hormone receptor (hr)-positive locally advanced or metastatic breast cancer (la/mbca) will have received endocrine therapy before disease progression. In the present study, we aimed to estimate the proportion of women with postmenopausal hr-positive la/mbca in the United States who are endocrine therapy-naive.

Methods: Women in the Optum Electronic Health Record (ehr) database with a breast cancer (bca) diagnosis (January 2008-March 2015) were included. Patient and malignancy characteristics were identified using structured data fields and natural-language processing of free-text clinical notes. The proportion of women with postmenopausal hr-positive, human epidermal growth factor 2 (her2)-negative (or unknown) la/mbca who had not received prior endocrine therapy was determined. Results were extrapolated to the entire U.S. population using the U.S. National Cancer Institute's Surveillance, Epidemiology, and End Results database. Results are presented descriptively.

Results: In the ehr database, 11,831 women with bca had discernible information on postmenopausal status, hr status, and disease stage. Of those women, 1923 (16.3%) had postmenopausal hr-positive, her2-negative (or unknown) la/mbca, and 70.7% of those 1923 patients (n = 1360) had not received prior endocrine therapy, accounting for 11.5% of the overall population. Extrapolating those estimates nationally suggests an annual incidence of 14,784 cases, and a 5-year limited duration prevalence of 50,638 cases.

Conclusions: A substantial proportion of women with postmenopausal hr-positive la/mbca in the United States could be endocrine therapy-naive.


Breast cancer, advanced, breast cancer, metastatic, electronic health records, endocrine therapy, hormone receptor–positive disease

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DOI of Published Version



Curr Oncol. 2019 Apr;26(2):e180-e187. doi: 10.3747/co.26.4163. Epub 2019 Apr 1. Link to article on publisher's site

Journal/Book/Conference Title

Current oncology

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Link to Article in PubMed

PubMed ID