1. Clinic of Gastroenterology, Nephrourology, and Surgery, Institute of Clinical Medicine, Faculty of Medicine, Vilnius University, 03101 Vilnius, Lithuania
2. Centre for Visceral Medicine and Translational Research, Faculty of Medicine, Institute of Clinical Medicine, Vilnius University, 03101 Vilnius, Lithuania
3. Upper Gastrointestinal Tract Surgery Department, North Estonia Medical Centre, 13419 Tallinn, Estonia
4. Upper Gastrointestinal Tumors Department, National Cancer Institute, 03022 Kyiv, Ukraine
5. Pathology Department, North Estonia Medical Centre, 13419 Tallinn, Estonia
6. Department of Abdominal Surgery and Oncology, National Cancer Institute, 08406 Vilnius, Lithuania