title: High rates of tumor growth and disease progression detected on serial pretreatment fluorodeoxyglucose-positron emission tomography/computed tomography scans in radical radiotherapy candidates with nonsmall cell lung cancer.
abstract: BACKGROUND
  The authors studied growth and progression of untreated nonsmall cell lung cancer (NSCLC) by comparing diagnostic and radiotherapy (RT) planning fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) scans before proposed radical chemo-RT.
  
  
  METHODS
  Patients enrolled on a prospective clinical trial were eligible for this analysis if they underwent 2 pretreatment whole body FDG-PET/CT scans, >7 days apart. Scan 1 was performed for diagnosis/disease staging and scan 2 for RT planning. Interscan comparisons included disease stage, metabolic characteristics, tumor doubling times, and change in treatment intent.
  
  
  RESULTS
  Eighty-two patients underwent planning PET/CT scans between October 2004 and February 2007. Of these, 28 patients (61% stage III, 18% stage II) had undergone prior staging PET/CT scans. The median interscan period was 24 days (range, 8-176 days). Interscan disease progression (TNM stage) was detected in 11 (39%) patients. The probability of upstaging within 24 days was calculated to be 32% (95% confidence interval [CI], 18%-49%). Treatment intent changed from curative to palliative in 8 (29%) cases, in 7 because of PET. For 17 patients who underwent serial PET/CT scans under standardized conditions, there was a mean relative interscan increase of 19% in tumor maximum standardized uptake value (SUV) (P=.022), 16% in average SUV (P=.004), and 116% in percentage injected dose (P=.002). Estimated doubling time of FDG avid tumor was 66 days (95% CI, 51-95 days).
  
  
  CONCLUSIONS
  Rapid tumor progression was detected in patients with untreated, predominantly stage III, NSCLC on serial FDG-PET/CT imaging, highlighting the need for prompt diagnosis, staging, and initiation of therapy in patients who are candidates for potentially curative therapy.
authors.affiliation: Department of Radiation Oncology, Radiation Therapy Services, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia. sarah.everitt@petermac.org
authors.forename: Sarah
authors.initials: S
authors.lastname: Everitt
authors.forename: Alan
authors.initials: A
authors.lastname: Herschtal
authors.forename: Jason
authors.initials: J
authors.lastname: Callahan
authors.forename: Nikki
authors.initials: N
authors.lastname: Plumridge
authors.forename: David
authors.initials: D
authors.lastname: Ball
authors.forename: Tomas
authors.initials: T
authors.lastname: Kron
authors.forename: Michal
authors.initials: M
authors.lastname: Schneider-Kolsky
authors.forename: David
authors.initials: D
authors.lastname: Binns
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Hicks
authors.forename: Michael
authors.initials: M
authors.lastname: MacManus
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D002986:Clinical Trials as Topic; D018450:Disease Progression; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011859:Radiography
chemical_list: D019788:Fluorodeoxyglucose F18