title: The influence of gastric filling instructions on dose delivery in patients with oesophageal cancer: A prospective study.
abstract: OBJECTIVE
  To evaluate whether adaptive radiotherapy for unaccounted stomach changes in patients with adenocarcinoma of the gastroesophageal junction (GEJ) is necessary and whether dose differences could be prevented by giving patients food and fluid instructions before treatment simulation and radiotherapy.
  
  
  METHODS
  Twenty patients were randomly assigned into two groups: patients with and without instructions about restricting food and fluid intake prior to radiotherapy simulation and treatment. Redelineation and offline recalculation of dose distributions based on cone-beam computed tomography (n=100) were performed. Dose-volume parameters were analysed for the clinical target volume extending into the stomach.
  
  
  RESULTS
  Four patients who did not receive instructions had a geometric miss (0.7-12 cm(3)) in only one fraction. With instructions, 3 out of 10 patients had a geometric miss (0.1-1.9 cm(3)) in one (n=2) or two (n=1) fractions. The V95% was reduced by more than 5% for one patient, but this underdosage was in an in-air region without further clinical importance.
  
  
  CONCLUSIONS
  Giving patients food and fluid instructions for the treatment of GEJ cancer offers no clinical benefit. Using a planning target volume margin of 1cm implies that there is no need for adaptive radiotherapy for GEJ tumours.
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands. Electronic address: Lien.vandevoorde@maastro.nl.
authors.forename: Lien
authors.initials: L
authors.lastname: Van De Voorde
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Ruben
authors.initials: R
authors.lastname: Larue
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Lucas
authors.initials: L
authors.lastname: Persoon
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Michel
authors.initials: M
authors.lastname: Öllers
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Sebastiaan
authors.initials: S
authors.lastname: Nijsten
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Geert
authors.initials: G
authors.lastname: Bosmans
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Maaike
authors.initials: M
authors.lastname: Berbée
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Ans
authors.initials: A
authors.lastname: Swinnen
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Wouter
authors.initials: W
authors.lastname: van Elmpt
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Ben
authors.initials: B
authors.lastname: Vanneste
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands; Medical Physics Unit, Department of Oncology, McGill University, Montréal, Canada.
authors.forename: Frank
authors.initials: F
authors.lastname: Verhaegen
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre+, The Netherlands.
authors.forename: Philippe
authors.initials: P
authors.lastname: Lambin
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000532:radiotherapy*; D054893:Cone-Beam Computed Tomography / Q000379:methods; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000532:radiotherapy*; D004943:Esophagogastric Junction; D005260:Female; D005746:Gastric Emptying / Q000502:physiology; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods
keywords: Adaptive radiotherapy; Dose-guided radiotherapy; Oesophageal cancer