title: Upper gastrointestinal tumors.
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Frank P
authors.initials: FP
authors.lastname: Vleggaar
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Siersema