title: Influence of FDG-PET on primary nodal target volume definition for head and neck carcinomas.
abstract: BACKGROUND
  The role of 2-[18F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in routine diagnostic staging remains controversial. In case of discordance between FDG-PET and CT, a compromise has to be made between the risk of false positive FDG-PET and the risk of delaying appropriate salvage intervention. Second, with intensity modulated radiation therapy (IMRT), smaller radiation fields allow tissue sparing, but could also lead to more marginal failures.
  
  
  METHODS
  We retrospectively studied 283 patients with head and neck carcinoma scheduled for radiotherapy between 2002 and 2010. We analyzed the influence of FDG-PET/CT versus CT alone on defining nodal target volume definition and evaluated its long-term clinical results. Second, the location of nodal recurrences was related to the radiation regional dose distribution.
  
  
  RESULTS
  In 92 patients, CT and FDG-PET, performed in mold, showed discordant results. In 33%, nodal staging was altered by FDG-PET. In 24%, FDG-PET also led to an alteration in nodal treatment, including a nodal upstage of 18% and downstage of 6%. In eight of these 92 patients, a regional recurrence occurred. Only two patients had a recurrence in the discordant node on FDG-PET and CT and both received a boost (high dose radiation).
  
  
  CONCLUSIONS
  These results support the complementary value of FDG-PET/CT compared to CT alone in defining nodal target volume definition for radiotherapy of head and neck cancer.
authors.affiliation: a Department of Otorhinolaryngology and Head & Neck Surgery , University Medical Center Utrecht , Utrecht , The Netherlands.
authors.forename: Sylvia L
authors.initials: SL
authors.lastname: van Egmond
authors.affiliation: a Department of Otorhinolaryngology and Head & Neck Surgery , University Medical Center Utrecht , Utrecht , The Netherlands.
authors.forename: Vera
authors.initials: V
authors.lastname: Piscaer
authors.affiliation: b Department Head and Neck Surgical Oncology , UMC Cancer Center, University Medical Center Utrecht , Utrecht , The Netherlands.
authors.forename: Luuk M
authors.initials: LM
authors.lastname: Janssen
authors.affiliation: a Department of Otorhinolaryngology and Head & Neck Surgery , University Medical Center Utrecht , Utrecht , The Netherlands.|c Rudolf Magnus Institute of Neuroscience , University Medical Center Utrecht , Utrecht , The Netherlands.
authors.forename: Inge
authors.initials: I
authors.lastname: Stegeman
authors.affiliation: d Department of Radiology and Nuclear Medicine , University Medical Center Utrecht , Utrecht , The Netherlands.
authors.forename: Monique G
authors.initials: MG
authors.lastname: Hobbelink
authors.affiliation: a Department of Otorhinolaryngology and Head & Neck Surgery , University Medical Center Utrecht , Utrecht , The Netherlands.|b Department Head and Neck Surgical Oncology , UMC Cancer Center, University Medical Center Utrecht , Utrecht , The Netherlands.
authors.forename: Wilko
authors.initials: W
authors.lastname: Grolman
authors.affiliation: e Department of Radiotherapy , University Medical Center Utrecht , Utrecht , The Netherlands.
authors.forename: Chris H
authors.initials: CH
authors.lastname: Terhaard
mesh_terms: D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D059186:Chemoradiotherapy, Adjuvant; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000008:administration & dosage; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D006801:Humans; D008297:Male; D037981:Neck Dissection; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy*; D009367:Neoplasm Staging; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods; D011829:Radiation Dosage; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated; D012189:Retrospective Studies; D016879:Salvage Therapy / Q000379:methods; D000077195:Squamous Cell Carcinoma of Head and Neck; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18