title: Prognostic significance of novel ¹⁸F-FDG PET/CT defined tumour variables in patients with oesophageal cancer.
abstract: OBJECTIVE
  (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) combined with computed tomography (PET/CT) is now established as a routine staging investigation of oesophageal cancer (OC). The aim of the study was to determine the prognostic significance of PET/CT defined tumour variables including maximum standardised uptake value (SUVmax), tumour length (TL), metastatic length of disease (MLoD), metabolic tumour volume (MTV), total lesion glycolysis (TLG) and total local nodal metastasis count (PET/CT LNMC).
  
  
  METHODS
  103 pre-treatment OC patients (76 adenocarcinoma, 25 squamous cell carcinoma, 1 poorly differentiated and 1 neuroendocrine tumour) were staged using PET/CT. The prognostic value of the measured tumour variables were tested using log-rank analysis of the Kaplan-Meier method and Cox's proportional hazards method. Primary outcome measure was survival from diagnosis.
  
  
  RESULTS
  Univariate analysis showed all variables to have strong statistical significance in relation to survival. Multivariate analysis demonstrated three variables that were significantly and independently associated with survival; MLoD (HR 1.035, 95% CI 1.008-1.064, p=0.011), TLG (HR 1.002, 95% CI 1.000-1.003, p=0.018) and PET/CT LNMC (HR 0.048-0.633, 95% CI 0.005-2.725, p=0.015).
  
  
  CONCLUSIONS
  MLoD, TLG, and PET/CT LNMC are important prognostic indicators in OC. This is the first study to demonstrate an independent statistical association between TLG, MLoD and survival by multivariable analysis, and highlights the value of staging OC patients with PET/CT using functional tumour variables.
authors.affiliation: Department of Radiology, University Hospital of Wales, Cardiff, UK. Electronic address: kfoley@doctors.org.uk.
authors.forename: Kieran G
authors.initials: KG
authors.lastname: Foley
authors.affiliation: Department of Wales Research & Diagnostic Positron Emission Tomography Imaging Centre (PETIC), University Hospital of Wales, Cardiff, UK. Electronic address: Patrick.Fielding@wales.nhs.uk.
authors.forename: Patrick
authors.initials: P
authors.lastname: Fielding
authors.affiliation: Department of Surgery, University Hospital of Wales, Cardiff, UK. Electronic address: Wyn.Lewis4@wales.nhs.uk.
authors.forename: Wyn G
authors.initials: WG
authors.lastname: Lewis
authors.affiliation: Department of Surgery, University Hospital of Wales, Cardiff, UK. Electronic address: alex_karran@hotmail.co.uk.
authors.forename: Alex
authors.initials: A
authors.lastname: Karran
authors.affiliation: Department of Surgery, University Hospital of Wales, Cardiff, UK. Electronic address: dcsy23@gmail.com.
authors.forename: David
authors.initials: D
authors.lastname: Chan
authors.affiliation: Department of Surgery, University Hospital of Wales, Cardiff, UK. Electronic address: pblake76@yahoo.co.uk.
authors.forename: Paul
authors.initials: P
authors.lastname: Blake
authors.affiliation: Department of Radiology, University Hospital of Wales, Cardiff, UK. Electronic address: Ashley.Roberts@wales.nhs.uk.
authors.forename: S Ashley
authors.initials: SA
authors.lastname: Roberts
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000473:pathology* / Q000556:secondary* / Q000628:therapy; D004938:Esophageal Neoplasms / Q000473:pathology* / Q000628:therapy; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Oesophageal cancer; PET/CT; Prognosis; Staging