title: 18F-FDG PET as a surrogate biomarker in non-small cell lung cancer treated with erlotinib: newly identified lesions are more informative than standardized uptake value.
abstract: This study assesses the predictive value of (18)F-FDG PET for overall survival in lung cancer patients treated with a targeted drug.
  
  
  METHODS
  (18)F-FDG PET was performed in 125 second- or third-line non-small cell lung cancer (NSCLC) patients with a baseline Eastern Cooperative Oncology Group performance status less than 3 before treatment with erlotinib (150 mg daily) and 2 wk into treatment. The predictive value of (18)F-FDG PET, clinical parameters, and epithelial growth factor receptor (EGFR) mutation status for survival duration was evaluated by fitting accelerated failure time models.
  
  
  RESULTS
  New lesions on PET at 2 wk, EGFR mutation status, performance status, and baseline tumor burden were independent and significant predictors of overall survival. Reduction of maximum standardized uptake value by at least 35% was predictive of survival only when EGFR mutation status was not accounted for.
  
  
  CONCLUSIONS
  (18)F-FDG PET in second- or third-line NSCLC patients at 2 wk after starting treatment with erlotinib carries information about overall survival. Parametric survival modeling enables a quantitative assessment of the predictive value of (18)F-FDG PET in the context of clinical and laboratory information. New-lesion status by (18)F-FDG PET at 2 wk is a potential surrogate biomarker for survival in NSCLC.
authors.affiliation: Biostatistics, Genentech Inc., South San Francisco, CA, USA. thomasgb@gene.com
authors.forename: Thomas
authors.initials: T
authors.lastname: Bengtsson
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Hicks
authors.forename: Amy
authors.initials: A
authors.lastname: Peterson
authors.forename: Ruediger E
authors.initials: RE
authors.lastname: Port
mesh_terms: D001692:Biological Transport; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000378:metabolism; D019008:Drug Resistance, Neoplasm; D000069347:Erlotinib Hydrochloride; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006801:Humans; D016013:Likelihood Functions; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011379:Prognosis; D011799:Quinazolines / Q000627:therapeutic use*; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D011799:Quinazolines; D019788:Fluorodeoxyglucose F18; D000069347:Erlotinib Hydrochloride