title: Early FDG PET at 10 or 20 Gy under chemoradiotherapy is prognostic for locoregional control and overall survival in patients with head and neck cancer.
abstract: OBJECTIVE
  Our study aimed to explore the optimal timing as well as the most appropriate prognostic parameter of (18)F-fluorodeoxyglucose positron emission tomography (FDG PET) during chemoradiotherapy (CRT) for an early prediction of outcome for patients with head and neck squamous cell carcinoma (HNSCC).
  
  
  METHODS
  Serial PET data (before and three times during CRT) of 37 patients with advanced stage HNSCC, receiving combined CRT between 2005 and 2009, were evaluated. The maximum standardized uptake value (SUV(max)), the average SUV (SUV(mean)) and the gross tumour volume determined by FDG PET (GTV PET), based on a source to background algorithm, were analysed. Stratified actuarial analysis was performed for overall survival (OS), disease-free survival (DFS) and locoregional control (LRC). The median follow-up time was 26 months (range 8-50).
  
  
  RESULTS
  For all patients, OS was 51%, DFS 44% and LRC 55% after 2 years. The 2-year OS (88%) and 2-year LRC (88%) were higher for patients whose SUV(max) of the primary tumour decreased 50% or more from the beginning (0 Gy) to week 1 or 2 (10 or 20 Gy) of CRT (ΔSUV(max10/20) ≥ 50%) than for patients with ΔSUV(max20) < 50% (2-year OS = 38%; p = 0.02; 2-year LRC 40%; p = 0.06). A pretreatment GTV PET below the median of 10.2 ml predicted a better 2-year OS (34% for GTV PET ≥ 10.2 ml vs 83% for GTV PET < 10.2 ml; p = 0.02).
  
  
  CONCLUSIONS
  The decrease of SUV(max) from before (0 Gy) to week 1 or 2 (10 or 20 Gy) of CRT is a potential prognostic marker for patients with HNSCC. Because GTV PET depends on the applied method of analysis, we suggest the use of SUV(max), especially ΔSUV(max10/20), for an early estimation of therapy outcome. Confirmatory studies are warranted.
authors.affiliation: Clinic and Polyclinic of Nuclear Medicine, Medical Faculty and University Hospital Carl Gustav Carus, Dresden University of Technology, Fetscherstraße 74, 01307 Dresden, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Hentschel
authors.forename: Steffen
authors.initials: S
authors.lastname: Appold
authors.forename: Andreas
authors.initials: A
authors.lastname: Schreiber
authors.forename: Nasreddin
authors.initials: N
authors.lastname: Abolmaali
authors.forename: Andrij
authors.initials: A
authors.lastname: Abramyuk
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dörr
authors.forename: Joerg
authors.initials: J
authors.lastname: Kotzerke
authors.forename: Michael
authors.initials: M
authors.lastname: Baumann
authors.forename: Klaus
authors.initials: K
authors.lastname: Zöphel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology* / Q000532:radiotherapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000532:radiotherapy; D049268:Positron-Emission Tomography / Q000379:methods*; D011829:Radiation Dosage; D013997:Time Factors; D016896:Treatment Outcome; D047368:Tumor Burden; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18