[1] Univ Verona, Digest Mol Clin Oncol Res Unit, Verona, Italy
[2] MHH, Dept Gastroenterol Hepatol & Endocrinol, Hannover, Germany
[3] Univ Padua, Unit Biostat Epidemiol & Publ Hlth, Dept Cardiac Thorac Vasc Sci & Publ Hlth, Padua, Italy
[4] Princess Margaret Canc Ctr, Div Gastroenterol & Hepatol, Toronto, ON, Canada