title: Chemoradiotherapy, the backbone of radiotherapy in gastrointestinal oncology.
authors.affiliation: Department of Radiation Oncology, University Medical Center Freiburg, Robert-Koch-Str. 3, Freiburg, Germany; German Cancer Consortium (DKTK), Freiburg, Germany; German Cancer Research Center (DKFZ), Heidelberg, Germany. Electronic address: thomas.brunner@uniklinik-freiburg.de.
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Brunner
authors.affiliation: Department of Internal Medicine I, Ulm University, Albert-Einstein-Allee 23, D-89081, Ulm, Germany. Electronic address: Thomas.seufferlein@uniklinik-ulm.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Seufferlein