1. Department of Internal Medicine University of Medicine and Pharmacy at Hochiminh City Ho Chi Minh Vietnam
2. Department of Endoscopy University Medical Center Ho Chi Minh Vietnam
3. Department of Gastroenterology Gia‐Dinh's People Hospital Ho Chi Minh Vietnam
4. Department of Gastroenterology Cho‐Ray Hospital Ho Chi Minh Vietnam
5. Department of Surgical Pathology University of Medicine and Pharmacy at Hochiminh City Ho Chi Minh Vietnam