title: Detection of extranodal spread in head and neck cancer with [18F]FDG PET and MRI: improved accuracy?
abstract: OBJECTIVE
  Preoperative detection of extranodal spread (ENS) in head and neck cancer can have important consequences for patient management. The aim of this study was to determine whether 18-fluorodeoxyglucose positron emission tomography ([18F]FDG PET) or a combination with Magnetic Resonance Imaging (MRI) could more accurately predict ENS, especially with the near availability of fully integrated [18F]FDG PET/MRI scanners.
  
  
  METHODS
  In retrospective cohort design a total of twelve patients, with 18 lymphnode metastases were studied with [18F]FDG PET and MRI. Presence of ENS was scored on MRI, and [18F]FDG PET images using a SUV max cut-off point of 12. Histopathology results were used as reference standard. Sensitivity, specificity and accuracy were calculated.
  
  
  RESULTS
  The sensitivity, specificity and accuracy of [18F]FDG PET for ENS reached 70%,100% and 83%, respectively. The mean SUVmax of ENS positive lymphnodes was 13.6 versus 8.7 for lymphnode metastases without ENS (P=0.03). The sensitivity, specificity and accuracy of MRI for ENS were 70%, 100% and 83%, respectively. When the [18F]FDG PET and MRI findings were combined sensitivity, specificity and accuracy were 80%, 100% and 89%, respectively. Thus, accuracy increased from 83% to 89%.
  
  
  CONCLUSIONS
  When there is no ENS or doubt of ENS on MRI, [18F]FDG PET seems to have additional value since it improves sensitivity and resolves uncertainty in case of high FDG uptake. This benefit needs to be confirmed prospectively in a larger cohort.
authors.affiliation: Department of Head and Neck Oncology and Surgery, Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam, The Netherlands - w.l.lodder@umcg.nl.
authors.forename: W L
authors.initials: WL
authors.lastname: Lodder
authors.forename: W V
authors.initials: WV
authors.lastname: Vogel
authors.forename: C A
authors.initials: CA
authors.lastname: Lange
authors.forename: O
authors.initials: O
authors.lastname: Hamming-Vrieze
authors.forename: M L
authors.initials: ML
authors.lastname: Van Velthuysen
authors.forename: F A
authors.initials: FA
authors.lastname: Pameijer
authors.forename: A J
authors.initials: AJ
authors.lastname: Balm
authors.forename: M W
authors.initials: MW
authors.lastname: Van Den Brekel
mesh_terms: D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000737:chemistry*; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D008207:Lymphatic Metastasis / Q000175:diagnosis / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D019275:Radiopharmaceuticals / Q000737:chemistry*; D012015:Reference Standards; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18