1. Department of Internal Medicine, King Hussein Cancer Center, Amman 11941, Jordan
2. Department of Internal Medicine, School of Medicine, The University of Jordan, Amman 11942, Jordan
3. Department of Radiology, King Hussein Cancer Center, Amman 11941, Jordan
4. Department of Radiation Oncology, King Hussein Cancer Center, Amman 11941, Jordan
5. Department of Radiation Oncology, Dalhousie University, Halifax, NS B3H 4R2, Canada