All Publications

  • Use of Gene Expression Profiling and Chemotherapy in Early-Stage Breast Cancer: A Study of Linked Electronic Medical Records, Cancer Registry Data, and Genomic Data Across Two Health Care Systems. Journal of oncology practice / American Society of Clinical Oncology Afghahi, A., Mathur, M., Thompson, C. A., Mitani, A., Rigdon, J., Desai, M., Yu, P. P., de Bruin, M. A., Seto, T., Olson, C., Kenkare, P., Gomez, S. L., Das, A. K., Luft, H. S., Sledge, G. W., Sing, A. P., Kurian, A. W. 2016


    The 21-gene recurrence score (RS) identifies patients with breast cancer who derive little benefit from chemotherapy; it may reduce unwarranted variability in the use of chemotherapy. We tested whether the use of RS seems to guide chemotherapy receipt across different cancer care settings.We developed a retrospective cohort of patients with breast cancer by using electronic medical record data from Stanford University (hereafter University) and Palo Alto Medical Foundation (hereafter Community) linked with demographic and staging data from the California Cancer Registry and RS results from the testing laboratory (Genomic Health Inc., Redwood City, CA). Multivariable analysis was performed to identify predictors of RS and chemotherapy use.In all, 10,125 patients with breast cancer were diagnosed in the University or Community systems from 2005 to 2011; 2,418 (23.9%) met RS guidelines criteria, of whom 15.6% received RS. RS was less often used for patients with involved lymph nodes, higher tumor grade, and age < 40 or ≥ 65 years. Among RS recipients, chemotherapy receipt was associated with a higher score (intermediate v low: odds ratio, 3.66; 95% CI, 1.94 to 6.91). A total of 293 patients (10.6%) received care in both health care systems (hereafter dual use); although receipt of RS was associated with dual use (v University: odds ratio, 1.73; 95% CI, 1.18 to 2.55), there was no difference in use of chemotherapy after RS by health care setting.Although there was greater use of RS for patients who sought care in more than one health care setting, use of chemotherapy followed RS guidance in University and Community health care systems. These results suggest that precision medicine may help optimize cancer treatment across health care settings.

    View details for DOI 10.1200/JOP.2015.009803

    View details for PubMedID 27221993

  • Chromosomal copy number alterations for associations of ductal carcinoma in situ with invasive breast cancer BREAST CANCER RESEARCH Afghahi, A., Forgo, E., Mitani, A. A., Desai, M., Varma, S., Seto, T., Rigdon, J., Jensen, K. C., Troxell, M. L., Gomez, S. L., Das, A. K., Beck, A. H., Kurian, A. W., West, R. B. 2015; 17
  • Breast Cancer Treatment Across Health Care Systems CANCER Kurian, A. W., Mitani, A., Desai, M., Yu, P. P., Seto, T., Weber, S. C., Olson, C., Kenkare, P., Gomez, S. L., de Bruin, M. A., Horst, K., Belkora, J., May, S. G., Frosch, D. L., Blayney, D. W., Luft, H. S., Das, A. K. 2014; 120 (1): 103-111

    View details for DOI 10.1002/cncr.28395

    View details for Web of Science ID 000328443000017

  • Oncoshare: lessons learned from building an integrated multi-institutional database for comparative effectiveness research. AMIA ... Annual Symposium proceedings / AMIA Symposium. AMIA Symposium Weber, S. C., Seto, T., Olson, C., Kenkare, P., Kurian, A. W., Das, A. K. 2012; 2012: 970-978


    Comparative effectiveness research (CER) using observational data requires informatics methods for the extraction, standardization, sharing, and integration of data derived from a variety of electronic sources. In the Oncoshare project, we have developed such methods as part of a collaborative multi-institutional CER study of patterns, predictors, and outcome of breast cancer care. In this paper, we present an evaluation of the approaches we undertook and the lessons we learned in building and validating the Oncoshare data resource. Specifically, we determined that 1) the state or regional cancer registry makes the most efficient starting point for determining inclusion of subjects; 2) the data dictionary should be based on existing registry standards, such as Surveillance, Epidemiology and End Results (SEER), when applicable; 3) the Social Security Administration Death Master File (SSA DMF), rather than clinical resources, provides standardized ascertainment of mortality outcomes; and 4) CER database development efforts, despite the immediate availability of electronic data, may take as long as two years to produce validated, reliable data for research. Through our efforts using these methods, Oncoshare integrates complex, longitudinal data from multiple electronic medical records and registries and provides a rich, validated resource for research on oncology care.

    View details for PubMedID 23304372