title: Is there a role for FGD-PET in radiotherapy planning in esophageal carcinoma?
abstract: OBJECTIVE
  To determine the additional value of FDG-positron emission tomography (PET) to optimize delineation of the clinical target volume (CTV) in patients with advanced esophageal carcinoma.
  
  
  METHODS
  The imaging and radiotherapy data from 30 patients with an advanced esophageal carcinoma were analysed. The lymph node classification for esophageal cancer was modified and translated into anatomical volumes on computed tomography (CT). The so defined 14 different regions were scored individually for lymph node involvement on CT, endoscopic ultrasound (EUS) and FDG-PET. The influence of discordant findings between conventional and functional imaging on the decision as to what should be irradiated was assessed.
  
  
  RESULTS
  In 14 of the 30 patients (47%) discordances were found in detection of the pathological lymph nodes between CT/EUS and FDG-PET. In 8 patients, 9 lymph node regions were found with pathologic nodes on conventional imaging only. In three of these patients the influence of FDG-PET findings would have led to a decrease of the irradiated volume. In 6 patients, 8 lymph node regions were found with a normal CT/EUS and pathologic nodes on FDG-PET. In three of these patients (10%) the influence of the FDG-PET would have led to enlargement of the irradiated volume.
  
  
  CONCLUSIONS
  The chance of a false negative result on FGD-PET is not negligible; therefore, the irradiated volume should not be reduced based on a negative FDG-PET in a region with suspect nodes on other investigations. However, due to the high specificity of FDG-PET enlarging the irradiated volume based on a positive FDG-PET in a region without suspected lymph nodes on CT and/or EUS should be considered. This indicates a role for FDG-PET in radiotherapy planning for esophageal cancer.
authors.affiliation: Department of Radiation Oncology, University Hospital Gasthuisberg, UZ Gasthuisberg, Herestraat 49, B-3000 Leuven, Belgium.
authors.forename: Olga
authors.initials: O
authors.lastname: Vrieze
authors.forename: Karin
authors.initials: K
authors.lastname: Haustermans
authors.forename: Walter
authors.initials: W
authors.lastname: De Wever
authors.forename: Toni
authors.initials: T
authors.lastname: Lerut
authors.forename: Eric
authors.initials: E
authors.lastname: Van Cutsem
authors.forename: Nadine
authors.initials: N
authors.lastname: Ectors
authors.forename: Martin
authors.initials: M
authors.lastname: Hiele
authors.forename: Patrick
authors.initials: P
authors.lastname: Flamen
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D019160:Endosonography; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D005188:False Negative Reactions; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010347:Patient Care Planning; D049268:Positron-Emission Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18