1. Department of Internal Medicine, Simmons Comprehensive Cancer Center, UT Southwestern Medical Center , Dallas, TX , United States
2. Department of Medicine, Vanderbilt University Medical Center , Nashville, TN , United States
3. Department of Genitourinary Medical Oncology, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center , Houston, TX , United States
4. Department of Medicine, Memorial Sloan Kettering Cancer Center , New York, NY , United States
5. EMD Serono, Inc. , Rockland, MA , United States , an affiliate of Merck KGaA
6. Princess Margaret Cancer Center, University of Toronto , Toronto, Ontario , Canada