title: Metabolic significance of the pattern, intensity and kinetics of 18F-FDG uptake in malignant pleural mesothelioma.
abstract: BACKGROUND
  Malignant pleural mesothelioma is an aggressive neoplasm with a highly variable course. This pilot study evaluated the significance of the pattern, intensity and kinetics of 18F-FDG uptake in mesothelioma in the context of histopathology and surgical staging.
  
  
  METHODS
  Sixteen consecutive patients with pleural disease on CT scan underwent 18F-FDG imaging. Imaging was performed with a dual detector gamma camera operating in coincidence mode. Semiquantitative image analysis was performed by obtaining lesion-to-background ratios (18F-FDG uptake index) and calculating the increment of 18F-FDG lesion uptake over time (malignant metabolic potential index (MMPi)).
  
  
  RESULTS
  Twelve patients had histologically proven malignant mesotheliomas (10 epithelial, two sarcomatoid). Thirty two lesions were positive for tumour. Patterns of uptake matched the extent of pleural and parenchymal involvement observed on CT scanning and surgery. Mean (SD) 18F-FDG uptake index for malignant lesions was 3.99 (1.92), range 1.5-9.46. Extrathoracic spread and metastases had higher 18F-FDG uptake indices (5.17 (2)) than primary (3.42 (1.52)) or nodal lesions (2.99 (1)). No correlation was found between histological grade and stage. The intensity of lesion uptake had poor correlation with histological grade but good correlation with surgical stage. 18F-FDG lesion uptake increased over time at a higher rate in patients with more advanced disease. The MMPi was a better predictor of disease aggressiveness than the histological grade.
  
  
  CONCLUSIONS
  This pilot study suggests that the pattern, intensity, and kinetics of 18F-FDG uptake in mesothelioma are good indicators of tumour aggressiveness and are superior to the histological grade in this regard.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. vgerbaudo@bics.bwh.harvard.edu
authors.forename: V H
authors.initials: VH
authors.lastname: Gerbaudo
authors.forename: S
authors.initials: S
authors.lastname: Britz-Cunningham
authors.forename: D J
authors.initials: DJ
authors.lastname: Sugarbaker
authors.forename: S T
authors.initials: ST
authors.lastname: Treves
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D015902:Gamma Cameras; D006801:Humans; D008297:Male; D008654:Mesothelioma / Q000000981:diagnostic imaging / Q000378:metabolism*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000378:metabolism; D009367:Neoplasm Staging / Q000379:methods; D010865:Pilot Projects; D010997:Pleural Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18