1. Alexandria Clinical Oncology Department, Alexandria University, Alexandria
2. Vihiga County and Referral Hospital, Vihiga County, Kenya
3. Department of Radiation Oncology, Loyola University Chicago, Loyola University Medical Center, Stritch School of Medicine, Cardinal Bernardin Cancer Center, Maywood, IL
4. Department of Clinical Oncology, Kafr Elsheikh University, Kafr Elsheikh, Egypt