title: Metabolic tumor volume is an independent prognostic factor in patients treated definitively for non-small-cell lung cancer.
abstract: OBJECTIVE
  Fluorine-18 flurodeoxyglucose positron emission tomography (FDG-PET) imaging has rapidly become the standard of care for staging patients with lung cancer. We evaluated the prognostic value of metabolic tumor volume (MTV), a measure of tumor burden on FDG-PET imaging, in patients with non-small-cell lung cancer (NSCLC) treated definitively.
  
  
  METHODS
  A retrospective review identified 61 patients with NSCLC who underwent FDG-PET imaging for pretreatment staging. Metabolically active tumor regions were segmented on the PET scans semiautomatically to calculate the total body MTV. We determined the relationship of overall survival (OS) and progression-free survival (PFS) with MTV in the entire cohort, and in the subgroup treated definitively.
  
  
  RESULTS
  The estimated median PFS and OS for the entire cohort were 11.1 months and 18.9 months. Higher MTV was significantly associated with worse OS (P = 0.00075) and PFS (P = 0.00077). For definitively treated patients, when MTV was analyzed as a binary value above or below the median value, 2-year PFS was 60% versus 39.7% (median PFS 34.9 vs. 11.9 months) and 2-year OS was 79.7% versus 33.3% (median OS 41.9 vs. 18.9 months), respectively (log-rank P = 0.12 for PFS and P = 0.066 for OS). When MTV was analyzed as a continuous variable, multivariate Cox proportional hazards analysis demonstrated a trend to worse PFS (hazard ratio [HR] = 1.31; P = 0.12) and significantly worse OS (HR = 1.53; P = 0.018) with increasing MTV after controlling for known prognostic variables.
  
  
  CONCLUSIONS
  Tumor burden as assessed by MTV yields prognostic information on survival beyond that of established prognostic factors in patients with NSCLC treated definitively.
authors.affiliation: Department of Radiation Oncology, Stanford University, CA.|Department of Radiation Oncology, David Geffen School of Medicine at UCLA, CA.
authors.forename: Percy
authors.initials: P
authors.lastname: Lee
authors.affiliation: Department of Radiation Oncology, Stanford University, CA.
authors.forename: Jose G
authors.initials: JG
authors.lastname: Bazan
authors.affiliation: Department of Health Research and Policy, Stanford University, CA.
authors.forename: Philip W
authors.initials: PW
authors.lastname: Lavori
authors.affiliation: Department of Radiation Oncology, Stanford University, CA.
authors.forename: Dilani K
authors.initials: DK
authors.lastname: Weerasuriya
authors.affiliation: Department of Radiology, Division of Nuclear Medicine, Stanford University, CA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Quon
authors.affiliation: Department of Radiation Oncology, Stanford University, CA.
authors.forename: Quynh-Thu
authors.initials: QT
authors.lastname: Le
authors.affiliation: Department of Medicine, Division of Oncology, Stanford University, CA.
authors.forename: Heather A
authors.initials: HA
authors.lastname: Wakelee
authors.affiliation: Department of Radiation Oncology, Stanford University, CA.
authors.forename: Edward E
authors.initials: EE
authors.lastname: Graves
authors.affiliation: Department of Radiation Oncology, Stanford University, CA.
authors.forename: Billy W
authors.initials: BW
authors.lastname: Loo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D047368:Tumor Burden
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18