1. Department of Radiation Oncology, University Hospitals, Case Western Reserve University, Cleveland, OH, USA
2. Centre for Clinical Epidemiology and Biostatistics, School of Medicine and Public Health, University of Newcastle, Newcastle, NSW, Australia
3. Department of Internal Medicine, North Shore-Long Island Jewish Medical Center, Manhasset, NY, USA
4. Division of Hematology/Oncology, Vidant Health Cancer Care, Greenville, NC, USA