title: Hypoxia imaging with [18F]-FMISO-PET for guided dose escalation with intensity-modulated radiotherapy in head-and-neck cancers.
abstract: OBJECTIVE
  Positron emission tomography (PET) with [(18)F]-fluoromisonidazole ([(18)F]-FMISO) provides a non-invasive assessment of hypoxia. The aim of this study is to assess the feasibility of a dose escalation with volumetric modulated arc therapy (VMAT) guided by [(18)F]-FMISO-PET for head-and-neck cancers (HNC).
  
  
  METHODS
  Ten patients with inoperable stages III-IV HNC underwent [(18)F]-FMISO-PET before radiotherapy. Hypoxic target volumes (HTV) were segmented automatically by using the fuzzy locally adaptive Bayesian method. Retrospectively, two VMAT plans were generated delivering 70 Gy to the gross tumour volume (GTV) defined on computed tomography simulation or 79.8 Gy to the HTV. A dosimetric comparison was performed, based on calculations of tumour control probability (TCP), normal tissue complication probability (NTCP) for the parotid glands and uncomplicated tumour control probability (UTCP).
  
  
  RESULTS
  The mean hypoxic fraction, defined as the ratio between the HTV and the GTV, was 0.18. The mean average dose for both parotids was 22.7 Gy and 25.5 Gy without and with dose escalation respectively. FMISO-guided dose escalation led to a mean increase of TCP, NTCP for both parotids and UTCP by 18.1, 4.6 and 8% respectively.
  
  
  CONCLUSIONS
  A dose escalation up to 79.8 Gy guided by [(18)F]-FMISO-PET with VMAT seems feasible with improvement of TCP and without excessive increase of NTCP for parotids.
authors.affiliation: Department of Radiotherapy, Institut Bergonié, 229, cours de l'Argonne, 33076, BORDEAUX Cedex, France, b.henriques@bordeaux.unicancer.fr.
authors.forename: B
authors.initials: B
authors.lastname: Henriques de Figueiredo
authors.forename: C
authors.initials: C
authors.lastname: Zacharatou
authors.forename: S
authors.initials: S
authors.lastname: Galland-Girodet
authors.forename: J
authors.initials: J
authors.lastname: Benech
authors.forename: H
authors.initials: H
authors.lastname: De Clermont-Gallerande
authors.forename: F
authors.initials: F
authors.lastname: Lamare
authors.forename: M
authors.initials: M
authors.lastname: Hatt
authors.forename: L
authors.initials: L
authors.lastname: Digue
authors.forename: E
authors.initials: E
authors.lastname: De Mones del Pujol
authors.forename: P
authors.initials: P
authors.lastname: Fernandez
mesh_terms: D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000532:radiotherapy*; D015687:Cell Hypoxia / Q000528:radiation effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008920:Misonidazole / Q000031:analogs & derivatives* / Q000627:therapeutic use; D009367:Neoplasm Staging; D010039:Otorhinolaryngologic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D049268:Positron-Emission Tomography; D011379:Prognosis; D011878:Radiotherapy / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D047368:Tumor Burden / Q000528:radiation effects
chemical_list: C031843:fluoromisonidazole; D008920:Misonidazole