1. Department of Surgery, Faculty of Medicine and Health Sciences, Andrzej Frycz Modrzewski Krakow University, 30-705 Kraków, Poland
2. Department of General, Oncological and Vascular Surgery, 5th Military Clinical Hospital in Kraków, 30-901 Kraków, Poland
3. Department of Medical Education, Jagiellonian University Medical College, 31-008 Kraków, Poland
4. National Institute of Oncology, Maria Skłodowska-Curie Memorial, 00-001 Warsaw, Poland