P Aswakul1, P Janyangdikul2, V Prachayakul3. 1. Liver and Digestive Institute, Samitivej Sukhumvit Hospital, Bangkok, Thailand. 2. Department of Pathology, Samitivej Srinakarin Hospital, Bangkok, Thailand. 3. Division of Gastroenterology, Department of Internal Medicine, Faculty of Medicine, Siriraj Hospital, Bangkok, Thailand.