1. Department of Surgery, School of Medicine, Karadeniz Technical University, Trabzon, Turkey;
2. Department of Radiology, School of Medicine, Karadeniz Technical University, Trabzon, Turkey;
3. Department of Gastroenterology, School of Medicine, Karadeniz Technical University, Trabzon, Turkey;
4. Department of Oncology, School of Medicine, Karadeniz Technical University, Trabzon, Turkey;
5. Department of Pathology, School of Medicine, Karadeniz Technical University, Trabzon, Turkey;
6. Department of Biostatistics, Hacettepe University, Ankara, Turkey