Treatment and Monitoring Variability in US Metastatic Breast Cancer Care

Abstract

PURPOSE Treatment and monitoring options for patients with metastatic breast cancer (MBC) are increasing, but little is known about variability in care. We sought to improve understanding of MBC care and its correlates by analyzing real-world claims data using a search engine with a novel query language to enable temporal electronic phenotyping. METHODS Using the Advanced Cohort Engine, we identified 6,180 women who met criteria for having estrogen receptor–positive, human epidermal growth factor receptor 2–negative MBC from IBM MarketScan US insurance claims (2007-2014). We characterized treatment, monitoring, and hospice usage, along with clinical and nonclinical factors affecting care. RESULTS We observed wide variability in treatment modality and monitoring across patients and geography. Most women received first-recorded therapy with endocrine (67%) versus chemotherapy, underwent more computed tomography (CT) (76%) than positron emission tomography-CT, and were monitored using tumor markers (58%). Nearly half (46%) met criteria for aggressive disease, which were associated with receiving chemotherapy first, monitoring primarily with CT, and more frequent imaging. Older age was associated with endocrine therapy first, less frequent imaging, and less use of tumor markers. After controlling for clinical factors, care strategies varied significantly by nonclinical factors (median regional income with first-recorded therapy and imaging type, geographic region with these and with imaging frequency and use of tumor markers; P < .0001). CONCLUSION Variability in US MBC care is explained by patient and disease factors and by nonclinical factors such as geographic region, suggesting that treatment decisions are influenced by local practice patterns and/or resources. A search engine designed to express complex electronic phenotypes from longitudinal patient records enables the identification of variability in patient care, helping to define disparities and areas for improvement.

Comparison of endocrine therapy and chemotherapy as different systemic treatment modes for metastatic luminal HER2-negative breast cancer patients —A retrospective study

“…A retrospective study of HR+HER-2-MBC by Gupta et al found that 53% of patients received advanced first-line chemotherapy, and 47% received advanced first-line endocrine therapy (15). Caswell-Jin et al showed that 43% of patients received first-line chemotherapy, and 67% received first-line endocrine therapy (16). We evaluated the systemic treatment options for HR+HER-2-MBC at a single hospital over the past 6 years and found that more than four-fifths of the patients received chemotherapy as first-line therapy, while less than 20% of the patients received endocrine therapy as first-line therapy.…”

“…However, there has been no prospective study analyzing the difference in efficacy between first-line chemotherapy and firstline endocrine therapy in HR+HER-2-MBC patients. Only a few retrospective studies have shown that chemotherapy is still the most common first-line palliative care for HR+HER-2-MBC (14)(15)(16)(17). Studies have shown that endocrine therapy and chemotherapy have similar progression-free survival (PFS) and overall survival (OS) outcomes (18-20).…”

Clinical Informatics Approaches to Understand and Address Cancer Disparities

“…Advances in electronic phenotyping are enabling scalable patient cohort creation and analysis to gain new insights into cancer disparities [17]. As an example, significant variability in metastatic breast cancer treatment and monitoring was observed across patient demographics and geographic region in a cohort of 6,180 U.S. women [18]. This cohort was identified via temporal data mining and the findings from the study suggest that, in addition to clinical factors, local resources and practice patterns influence individual treatment decisions.…”

Differences in Outcomes Between Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Metastatic Breast Cancer Patients in Upper Middle-Income versus High-Income Countries: A Retrospective Study from 4 Oncology Centers

“…Patients with mBC have an increasing number of well-known options for therapy and condition monitoring, but little is known about how different types of care are delivered [ 13 ]. Access to healthcare facilities is restricted in low- and middle-income nations, and most patients do not even have access to dual anti-HER2 medication [ 14 ].…”