1 Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan; School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan; National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan.
2 National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan; Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan; Centre for Cancer Research, Kaohsiung Medical University, Kaohsiung, Taiwan. Electronic address: leochen@nhri.org.tw.