Advances in a wide array of scientific technologies have brought data of unprecedented volume and complexity into the oncology research space. These novel big data resources are applied across a variety of contexts—from health services research using data from insurance claims, cancer registries, and electronic health records, to deeper and broader genomic characterizations of disease. Several forms of big data show promise for improving our understanding of racial disparities in breast cancer, and for powering more intelligent and far-reaching interventions to close the racial gap in breast cancer survival. In this article we introduce several major types of big data used in breast cancer disparities research, highlight important findings to date, and discuss how big data may transform breast cancer disparities research in ways that lead to meaningful, lifesaving changes in breast cancer screening and treatment. We also discuss key challenges that may hinder progress in using big data for cancer disparities research and quality improvement.
New Frontiers in Big Data Research: Leveraging Comprehensive Patient Data
Vast amounts of patient data are collected as part of the process of making a diagnosis and administering clinical care. Unfortunately, much of these data exist within discrete and closed information technology systems, and are not easily available to researchers or clinicians seeking to learn from this pooled patient experience. These systems also often contain specific proprietary and non-universal coding nomenclatures or ontologies (eg, CPT [Current Procedural Terminology], LOINC [Logical Observation Identifiers Names and Codes]). For example, information about a given patient’s disease progression or choice of treatment as recoded by clinic notes is captured as unstructured or “free text” data in the EHR and must be restructured and systematically organized for research. Imaging and laboratory information are stored as external images or files that require special software for viewing. Health insurance claims and structured data on diagnosis and procedures are collected from practice and insurance management systems. The mutually exclusive nature of these data systems makes it very difficult to consolidate a complete body of information on an individual patient. The construction of a clinically meaningful “big data” picture of a patient becomes even more complicated as patients move between different providers, clinics, and health systems for diagnoses, treatment, and follow-up care. The field of genomics has benefited from rapid advances in data computing, storage, and analysis but the data remain largely outside the scope of other clinical and computing information systems.
Oncology practices are critical players in the future of big data cancer research. Only with strong participation from both community and academic practices will we be able to fully understand the diversity of disease and related health disparities. Data infrastructure programs such as the American Society of Clinical Oncology’s CancerLinQ initiative and Flatiron Health are able to partner directly with oncology practices and can adapt to different EHR platforms. The NCI Community Oncology Research Program (NCORP) of the National Cancer Institute is also a highly successful federally supported resource that helps to support clinical trial participation in community oncology practice. The predecessor to the NCORP program (the NCI Community Clinical Oncology, or CCOP, program) was effective at helping to diffuse cancer innovation more quickly into community practices and attenuate disparities in the receipt of treatment.[12,14,39,40] In addition to participating in data infrastructure platforms, practicing oncologists are critical stakeholders for patient reporting and disseminating new evidence regarding precision medicine and tumor heterogeneity into real-world practice.
The overarching vision is to create a “learning health system” in which data from real-world cancer patients within the EHR and data from other systems are rapidly analyzed and fed back to the physicians at the point of care. The ultimate goal is to improve the quality of cancer care by using big data and analytics in real time to analyze patient data within a larger context; this approach enables more precise tailoring of treatment and timely delivery of treatment outcomes information to clinicians.
Key Challenges in Applying Big Data to Cancer Disparities Research
Key challenges of using big data resources for cancer disparities research are similar to those complicating use of big data for other goals in cancer care. These challenges can be summarized as follows:
• Data structure and format are not standardized among different systems, significantly complicating the combination of data from multiple sources.
• Information technicians and systems scientists are struggling to develop comprehensive technology platforms that can integrate data across multiple scales and scientific domains (from molecular data to social/behavioral risk factors).
• Large amounts of critical data (eg, cancer stage, recurrence) are trapped in unstructured data fields and require sophisticated human-curation and/or natural language processing approaches to render them usable.
• Gaps exist in data continuity and longitudinal follow-up when portions of patients’ care occur outside of a system, such as a participating provider, clinic, EHR, laboratory, or payer.
While various governmental, academic, and for-profit companies have all initiated big data endeavors, there has been a lack of significant collaboration and data sharing between initiatives. Data use agreements, regulatory measures, and data governance processes, while acting as key safeguards to patient privacy and data security, have hampered efforts at broader sharing of data. Examples of innovations that would ease collaborative sharing of big data in oncology include greater investment by data partners in secure data sharing infrastructures and the use of unified patient identifiers to recognize patients across systems.
- Big data that are relevant for oncology disparities research exist in a variety of formats; these include administrative claims, national cancer registries, electronic health records, and genomic data.
- Big data for oncology disparities research are united by their volume, complexity, and requirements for novel technological and analytic methods in order to extract useful and reliable information.
- Analyses based on big data can be compromised when researchers fail to understand the populations, biases, and limitations, as well as the strengths, of each unique data resource. However, analyses can be strengthened and made more representative of vulnerable populations if resources are linked together to offset these limitations.
- The next frontiers of big data research in oncology require increasing collaboration among interdisciplinary teams of clinical, laboratory, and information technology, as well as statistical experts willing to share methods and data between fields in secure, standardized ways.
An additional challenge that is specific to disparities research is the generalizability of patients captured within big data resources. Patients at large centers with sophisticated EHR systems and data-sharing capabilities, even those who belong to minority groups, may differ significantly from minority patients in lower-resource settings, which may not readily share data or leverage electronic resources and/or technology. Likewise, biologic discovery efforts tend to focus on patients with large tumors and ample genomic material for use in multiple genotyping/sequencing platforms. These large tumors, sampled from mostly academic research centers, may not capture the diversity of cases in a broader setting. Thus, study design and possible selection biases should be considered when evaluating and drawing inferences from big data initiatives. It is possible that some of these selection biases shift the frequency of specific tumor types or specific treatment care patterns, but consequences can also be more profound. As the promise of big data is transformed into interventions that improve care quality or close care gaps, disparities could widen if minority patients and minority-serving healthcare providers are not represented in research or infrastructure-building efforts. Special attention and emphasis within big data research are warranted so that information derived from, and specific insights into, minority populations are adequately represented.
The Future: Big Data–Driven Interventions
Research in other cancer types has demonstrated that knowledge derived from big data can transform clinical care and/or lead to new interventions. In the translation of complex, high-dimensional genomic data into precision medicine tests, breast cancer has been an early success story, with several genomic assays already available as treatment decision-making aids. In contrast, no published intervention has used health services big data resources to improve breast cancer care, but templates are available for such efforts in other cancer types. For example, the Michigan Urological Surgery Improvement Collaborative has effectively leveraged EHR and claims data together with other data resources to directly inform providers about practice patterns, improve adherence to guidelines, and optimize patient treatment.[42,43] In North Carolina, the big data infrastructure of the ICISS has been used to identify or verify “hot spots” of low rates of colorectal cancer screening and high racial disparities in morbidity and mortality. These hotspotting data were used to simulate the effect of different intervention scenarios, which led to an ongoing intervention specifically aimed to reduce disparities in screening.[44,45] The ongoing ACCURE (Accountability for Cancer Care Through Undoing Racism and Equity) intervention uses an electronic alert system linked to the EHR, along with patient navigation and community-based participatory research, to decrease disparities between black patients and white patients in terms of receipt of timely care for breast and lung cancer; results have not yet been reported. A critical component of successful interventions to address disparities in cancer care is a strong interdisciplinary approach to the entire “lifecycle” of the project (Figure 2). Clinical oncology experts must work in close harmony with data and software engineers to store and manage the data. Additionally, the research scientists and analysts coaxing valuable and actionable information from these large systems need to have close working relationships and intimate knowledge of the clinical data processes that generated their analytic files. Integration of biological data and access data across multiple scales also requires a team approach that employs a wide range of expertise. Exploiting the power of the rich breast cancer disparities data available will require teams that have collective expertise in the areas of clinical oncology, computer science, molecular biology, statistical analysis, and population science, and that can flexibly tackle new methodological challenges as they arise.
Financial Disclosure: Dr. Meyer is a data and methods consultant to, and serves on the advisory board of, Merck. The other authors have no significant financial interest in or other relationship with the manufacturer of any product or provider of any service mentioned in this article.
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