title: Prognostic value of 18F-FDG PET image-based parameters in oesophageal cancer and impact of tumour delineation methodology.
abstract: OBJECTIVE
  (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) image-derived parameters, such as standardized uptake value (SUV), functional tumour length (TL) and tumour volume (TV) or total lesion glycolysis (TLG), may be useful for determining prognosis in patients with oesophageal carcinoma. The objectives of this work were to investigate the prognostic value of these indices in oesophageal cancer patients undergoing combined chemoradiotherapy treatment and the impact of TV delineation strategies.
  
  
  METHODS
  A total of 45 patients were retrospectively analysed. Tumours were delineated on pretreatment (18)F-FDG scans using adaptive threshold and automatic (fuzzy locally adaptive Bayesian, FLAB) methodologies. The maximum standardized uptake value (SUV(max)), SUV(peak), SUV(mean), TL, TV and TLG were computed. The prognostic value of each parameter for overall survival was investigated using Kaplan-Meier and Cox regression models for univariate and multivariate analyses, respectively.
  
  
  RESULTS
  Large differences were observed between methodologies (from -140 to +50% for TV). SUV measurements were not significant prognostic factors for overall survival, whereas TV, TL and TLG were, irrespective of the segmentation strategy. After multivariate analysis including standard tumour staging, only TV (p < 0.002) and TL (p = 0.042) determined using FLAB were independent prognostic factors.
  
  
  CONCLUSIONS
  Whereas no SUV measurement was a significant prognostic factor, TV, TL and TLG were significant prognostic factors for overall survival, irrespective of the delineation methodology. Only functional TV and TL derived using FLAB were independent prognostic factors, highlighting the need for accurate and robust PET tumour delineation tools for oncology applications.
authors.affiliation: INSERM, U650 LaTIM, CHU Morvan, 5 Avenue Foch, 29609 Brest, France. hatt@univ-brest.fr
authors.forename: Mathieu
authors.initials: M
authors.lastname: Hatt
authors.forename: Dimitris
authors.initials: D
authors.lastname: Visvikis
authors.forename: Nidal M
authors.initials: NM
authors.lastname: Albarghach
authors.forename: Florent
authors.initials: F
authors.lastname: Tixier
authors.forename: Olivier
authors.initials: O
authors.lastname: Pradier
authors.forename: Catherine
authors.initials: C
authors.lastname: Cheze-le Rest
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011379:Prognosis; D012189:Retrospective Studies; D016019:Survival Analysis; D047368:Tumor Burden
chemical_list: D019788:Fluorodeoxyglucose F18