title: The impact of respiratory gated positron emission tomography on clinical staging and management of patients with lung cancer.
abstract: OBJECTIVE
  Respiratory motion artefacts during positron emission tomography (PET) deteriorate image quality, potentially introducing diagnostic uncertainties. The objective of this study was to determine the impact of optimal respiratory gating on clinical staging and management of patients with primary lung cancer.
  
  
  METHODS
  From our fast-track outpatient diagnostic program, 55 patients with primary lung cancer, who underwent whole body [(18)F]-fluorodeoxyglucose (FDG) PET, were included. Respiratory gating was performed on bed positions covering the thorax and abdomen. Independent reading was conducted by two nuclear medicine physicians. The observers scored the number and anatomical location of the lesions, lymph node basins and the presence of distant metastasis in non-gated and gated images. A tumor (T), lymph node (N), and metastasis (M) stage was assigned to each patient according to the 7th revision of the TNM classification. Staging accuracy was determined using histopathological data and follow-up CT imaging. In addition, a management plan was created for each patient based on non-gated and gated images by an experienced pulmonologist.
  
  
  RESULTS
  For nuclear medicine physician 1 and 2, respiratory gating resulted in detection of more lesions in five and eight patients (9% and 15%) respectively. However, this did not result in any migration in T or M-stage. Migration in N-stage was observed in four and seven patients (7% and 13%) for nuclear medicine physician 1 and 2 respectively. Staging accuracy was slightly improved when respiratory gating was performed. Furthermore, there was substantial agreement in patient management between non-gated and gated images.
  
  
  CONCLUSIONS
  Respiratory gating improved staging accuracy, mainly in assessment of lymph node involvement. However, the effect on patient management was limited due to the presence of already advanced disease stage in many patients. These findings suggest that the expected impact of respiratory gating will be solely on management of patients with early disease.
authors.affiliation: Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands. Electronic address: Willem.Grootjans@Radboudumc.nl.
authors.forename: Willem
authors.initials: W
authors.lastname: Grootjans
authors.affiliation: Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands.
authors.forename: Rick
authors.initials: R
authors.lastname: Hermsen
authors.affiliation: Department of Pulmonary Diseases, Radboud university medical center, Nijmegen, The Netherlands.
authors.forename: Erik H F M
authors.initials: EH
authors.lastname: van der Heijden
authors.affiliation: Department of Pulmonary Diseases, Radboud university medical center, Nijmegen, The Netherlands.
authors.forename: Olga C J
authors.initials: OC
authors.lastname: Schuurbiers-Siebers
authors.affiliation: Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands.
authors.forename: Eric P
authors.initials: EP
authors.lastname: Visser
authors.affiliation: Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands; The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK.
authors.forename: Wim J G
authors.initials: WJ
authors.lastname: Oyen
authors.affiliation: Department of Radiology and Nuclear Medicine, Radboud university medical center, Nijmegen, The Netherlands; Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Lioe-Fee
authors.initials: LF
authors.lastname: de Geus-Oei
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000008:administration & dosage; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods; D019275:Radiopharmaceuticals / Q000008:administration & dosage
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Lung cancer; Optimal respiratory gating; PET/CT; Patient management; [(18)F]fluorodeoxyglucose