[1] Khoo Teck Puat Hosp, Div Gastroenterol, Dept Med, Singapore, Singapore
[2] Singapore Gen Hosp, Dept Gastroenterol & Hepatol, Singapore, Singapore
[3] Singapore Gen Hosp, Dept Anat Pathol, Singapore, Singapore
[4] Duke NUS Med Sch, Singapore, Singapore
[5] ASTAR, Inst Mol Cell Biol, Singapore, Singapore