title: Use of computed tomography and positron emission tomography/computed tomography for staging of local extent in patients with malignant pleural mesothelioma.
abstract: OBJECTIVE
  The objective of this study was to determine the diagnostic value of computed tomography (CT) and positron emission tomography (PET)/CT for staging of malignant pleural mesothelioma (MPM) in patients undergoing induction chemotherapy.
  
  
  METHODS
  Sixty-two patients (median age, 61 years; female: n = 9) with proven MPM underwent CT after induction chemotherapy. Of these, 28 underwent additional PET/CT. Extrapleural pneumonectomy was performed for pathological TNM staging. Clinical TNM stage was assessed by 3 independent readers. Relative and absolute underestimation and overestimation were compared with pathological tumor stage. Sensitivity, specificity, and accuracy for differentiation between stages T2 and T3 were assessed. Interobserver agreement between the readers was analyzed (κ).
  
  
  RESULTS
  Positron emission tomography/CT and CT underestimated T stage in up to 30% of the cases. Positron emission tomography/CT had a higher accuracy for tumor extent compared with CT (PET/CT: 0.92; CT: 0.84). The accuracy for nodal staging was higher for CT than for PET/CT (PET/CT: 0.78; CT: 0.87). Concerning International Mesothelioma Interest Group classification, PET/CT improved the accuracy of preoperative staging compared with CT (PET/CT: 0.91; CT: 0.82). Interobserver agreement was moderate for CT (0.48-0.62) and good for PET/CT (0.64-0.83) for T staging. For nodal staging, interobserver agreement was fair to moderate for CT and good for PET/CT (CT: 0.37-0.51; PET/CT: 0.73-0.76).
  
  
  CONCLUSIONS
  Positron emission tomography/CT is more accurate and has a lower interobserver variability for clinical intrathoracic staging of MPM compared with CT. Nevertheless PET/CT underestimated tumor stage in a substantial number of cases, showing the need for a more accurate imaging technology or approach.
authors.affiliation: From the *Institute of Diagnostic and Interventional Radiology, †Division of Thoracic Surgery, ‡Clinic of Nuclear Medicine, and §Clinic of Oncology, University Hospital of Zurich, Zurich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Frauenfelder
authors.forename: Peter
authors.initials: P
authors.lastname: Kestenholz
authors.forename: Roger
authors.initials: R
authors.lastname: Hunziker
authors.forename: Thi Dan Linh
authors.initials: TD
authors.lastname: Nguyen
authors.forename: Martina
authors.initials: M
authors.lastname: Fries
authors.forename: Patrick
authors.initials: P
authors.lastname: Veit-Haibach
authors.forename: Lars
authors.initials: L
authors.lastname: Husmann
authors.forename: Rolf
authors.initials: R
authors.lastname: Stahel
authors.forename: Walter
authors.initials: W
authors.lastname: Weder
authors.forename: Isabelle
authors.initials: I
authors.lastname: Opitz
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000188:drug therapy; D008297:Male; D008654:Mesothelioma / Q000175:diagnosis* / Q000188:drug therapy; D000086002:Mesothelioma, Malignant; D008875:Middle Aged; D064847:Multimodal Imaging; D009367:Neoplasm Staging / Q000379:methods; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed