title: Use of single MRI and 18F-FDG PET-CT scans in both diagnosis and radiotherapy treatment planning in patients with head and neck cancer: advantage on target volume and critical organ delineation.
abstract: BACKGROUND
  The use of a single MRI and 18F-fluoro deoxyglucose positron emission tomography-CT (18F-FDG PET-CT) was evaluated, both in diagnostic procedure and radiotherapy planning, in patients with head and neck cancer.
  
  
  METHODS
  Thirty-five patients with nasopharyngeal and oropharyngeal tumors were studied. The MRI and 18F-FDG PET-CT were used for both diagnostic work-up and gross tumor volume and critical structure delineation. The interobserver variation (IOV) of volumes determined on MRI and CT by a radiotherapist and by a radiologist were compared as well as their impact on dose distribution.
  
  
  RESULTS
  The CT-MRI decreased the IOV of parotid glands in 12 of 35 and target volume in 15 of 35 patients. The use of 18F-FDG PET-CT changed the treatment design in 6 of 21 patients.
  
  
  CONCLUSIONS
  Diagnostic imaging performed in the treatment position can improve the accuracy of radiotherapy planning in case of intracranial tumor extension, heavy dental work, or contraindication for contrast-enhanced CT, but not in the absence of these conditions.
authors.affiliation: Service de Radiothérapie, Centre René Huguenin, Saint-Cloud, France. gardner@crhl.org
authors.forename: Miriam
authors.initials: M
authors.lastname: Gardner
authors.forename: Philippe
authors.initials: P
authors.lastname: Halimi
authors.forename: Danielle
authors.initials: D
authors.lastname: Valinta
authors.forename: Marie-Madeleine
authors.initials: MM
authors.lastname: Plantet
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Alberini
authors.forename: Myriam
authors.initials: M
authors.lastname: Wartski
authors.forename: Alain
authors.initials: A
authors.lastname: Banal
authors.forename: Stephane
authors.initials: S
authors.lastname: Hans
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Floiras
authors.forename: Martin
authors.initials: M
authors.lastname: Housset
authors.forename: Alain
authors.initials: A
authors.lastname: Labib
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000175:diagnosis / Q000532:radiotherapy*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000532:radiotherapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D009959:Oropharyngeal Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D010306:Parotid Gland / Q000000981:diagnostic imaging / Q000473:pathology / Q000528:radiation effects; D019275:Radiopharmaceuticals; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18