1. University Hospital Center “Mother Teresa”, Department of Pathology, Rruga e Dibrës 372, Tirana, Albania
2. Endoscopic Clinic “La Vita”, Rruga ‘Xhanfize Keko’ 13, Tirana, Albania
3. University Hospital Center “Mother Teresa”, Department of Surgery, Rruga e Dibrës 372, Tirana, Albania
4. University of Bergen, Faculty of Medicine and Dentistry, Department of Global Public Health and Primary Care, Kalfarveien 31, Bergen, 5018, Norway