1. Department of Radiation Oncology, King Hussein Cancer Center, Amman, Jordan
2. Department of Surgical Oncology, King Hussein Cancer Center, Amman, Jordan
3. Division of Hematology/Oncology, Department of Internal Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, Unites States
4. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, University of Toronto, ON, Canada