1. The Johns Hopkins University School of Medicine, Baltimore, Maryland.
2. University of Michigan Medical Center, Ann Arbor, Michigan.
3. University of Colorado Health Sciences Center, Denver, Colorado.
4. The Ohio State University, Columbus, Ohio.
5. Boston University Medical Center, Boston, Massachusetts.
6. University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania.
7. University of Florida College of Medicine, Gainesville, Florida.
8. The Mayo Clinic, Rochester, Minnesota.
9. The University of Siena, Siena, Italy.
10. Institute Gustave Roussy, Paris, France.
11. University of Texas M.D. Anderson Cancer Center, Houston, Texas.
12. University of Cincinnati Medical Center, Cincinnati, Ohio.
13. Memorial Sloan-Kettering Cancer Center, New York, New York.