1. Department of Medicine, University of California San Francisco , San Francisco, CA 94143 , United States
2. Medical Services, San Francisco Veterans Affairs Health Care System , San Francisco, CA 94121 , United States
3. California Pacific Medical Center Research Institute , San Francisco, CA 94107 , United States
4. The Campbell Family Institute for Breast Cancer Research, Princess Margaret Cancer Centre, University Health Network , Toronto, ON M5G 2M9 , Canada
5. Department of Surgery, University of California San Francisco , San Francisco, CA 94143 , United States
6. Surgical Services, San Francisco Veterans Affairs Health Care System , San Francisco, CA 94121 , United States
7. Department of Epidemiology and Biostatistics, University of California San Francisco , San Francisco, CA 94143 , United States