1. VA Boston Healthcare System, Boston, MA;
2. Department of Medicine, Harvard Medical School, Boston, MA;
3. Dana-Farber Cancer Institute, Boston, MA;
4. St. Joseph Hospital, Nashua, NH;
5. Michael E. DeBakey VA Medical Center, Houston, TX;
6. Department of Medicine, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX; and
7. Boston University School of Medicine, Boston, MA