1. Osmangazi University Faculty of Medicine, Department of Radiation Oncology, Eskişehir, Turkey
2. Ali Osman Sönmez Oncology Hospital, Department of Medical Oncology, Bursa, Turkey
3. Osmangazi University Faculty of Medicine, Department of Biostatistics, Eskişehir, Turkey
4. Ankara University Faculty of Medicine, Department of Radiation Oncology, Ankara, Turkey