San Francisco Bay Area: Stanford University

Dr. Esther John, Principal Investigator

Dr. John received both her PhD (in 1990) and MSPH (in 1987) in Epidemiology from the University of North Carolina at Chapel Hill.

Dr. John is Professor of Epidemiology & Population Health and of Medicine (Oncology), and co-leader of the Population Sciences Program of the Stanford Cancer Institute. Her research program is focused on identifying the causes of breast cancer and prostate cancer, with a special interest in the role of potentially modifiable lifestyle factors (physical activity, obesity, vitamin D, dietary factors), early life exposures, and genetic susceptibility. Many of her research studies are focused on Latina and African American populations and investigate racial/ethnic differences in risk factors and their contribution to cancer disparities.

Dr. John is a Senior Research Scientist at the Cancer Prevention Institute of California in Fremont, CA, Consulting Professor at the Stanford University School of Medicine (Department of Health Research and Policy), and member of the Stanford Cancer Institute.


Dr. Theresa Keegan, Co-Investigator

Dr. Keegan received her PhD in Epidemiology from Stanford University in 2003, after receiving her MS in Wellness Management from Ball State University in 1999.

Dr. Keegan is particularly interested in modifiable factors and health behaviors that influence the occurrence of cancer and survival after cancer, and was funded to assess the relationship of life-time body size and physical activity to risk of Hodgkin lymphoma, and to assess the impact of the neighborhood built environment on the risk of breast cancer and survival after breast cancer. Dr. Keegan’s research also focuses on cancer surveillance, cancer outcomes and cancer survivorship, particularly among adolescents and young adults 15 to 39 years of age.  She has worked extensively with population-based cancer registry data to understand patterns of cancer incidence, treatment and survival, and been involved with multiple studies examining patient experiences with cancer and patient-reported outcomes after cancer diagnosis.

Dr. Keegan is an Associate Professor in the Division of Hematology and Oncology at the University of California (UC) Davis School of Medicine and a member of the UC Davis Comprehensive Cancer Center.


Jenny Nguyen, MPH, Research Coordinator

Jenny Nguyen is a Research Coordinator for the LEGACY Girls Study in California. She supports a variety of research activities including monitoring the flow of questionnaire mailings, tracking follow-up activities, preparing reports, and maintaining quality control of data. She joined LEGACY in the summer of 2012 while pursuing her graduate degree. Since then, she has earned her Master of Public Health degree from the University of San Francisco in the Fall of 2014 and wishes to continue on to pursue a doctorate degree. Outside of work, Jenny enjoys exploring new hiking trails, going to concerts, reading books, traveling, and spending time with her family and friends.




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