title: Accuracy and predictive features of FDG-PET/CT and CT for diagnosis of lymph node metastasis of T1 non-small-cell lung cancer manifesting as a subsolid nodule.
abstract: OBJECTIVE
  To retrospectively evaluate the diagnostic accuracy and predictive features of F-18 fluorodeoxyglucose positron emission tomography/ computed tomography (FDG-PET/CT) and CT in lymph node (LN) staging of T1 non-small-cell lung cancers (NSCLCs) manifesting as subsolid nodules.
  
  
  METHODS
  From January 2005 to May 2011, 160 patients with pathologically proven T1 subsolid NSCLCs with LN staging were included in this study. Diagnostic accuracies of FDG-PET/CT and CT for LN staging were evaluated. Maximum standardised uptake value (SUVmax) and CT features of primary tumours were evaluated to investigate predictive factors for LN metastasis.
  
  
  RESULTS
  LN metastases were found in nine of the 160 patients (5.6%). No LN metastasis was present in patients with a solid proportion ≤50%. Sensitivity, specificity and accuracy of FDG-PET/CT for LN staging on a per-patient basis were 11.1%, 86.1% and 81.9%; those of CT were 11.1%, 96.7% and 91.9%. Among patients with a solid proportion >50%, there were significant differences in SUVmax, solid portion size, solid proportion and lesion location between patients with and without LN metastasis. Multivariate analysis revealed that higher SUVmax, a larger solid proportion and central location were independent predictors of LN metastasis.
  
  
  CONCLUSIONS
  FDG-PET/CT adds little value to CT in the lymph node staging of T1 subsolid NSCLCs.
  
  
  CONCLUSIONS
  Lymph node (LN) metastases are important in non-small-cell lung cancer (NSCLC). • Positron emission tomography (PET) helps to stage solid NSCLCs. • FDG-PET/CT adds little to the LN staging of T1 subsolid NSCLCs. • No LN metastasis in patients with a solid proportion ≤50%. • LN metastasis is more common in solid and/or centrally sited tumours.
authors.affiliation: Department of Radiology, Seoul National University College of Medicine, 101, Daehangno, Jongno-gu, Seoul, 110-744, Korea.
authors.forename: Sang Min
authors.initials: SM
authors.lastname: Lee
authors.forename: Chang Min
authors.initials: CM
authors.lastname: Park
authors.forename: Jin Chul
authors.initials: JC
authors.lastname: Paeng
authors.forename: Hyung Jun
authors.initials: HJ
authors.lastname: Im
authors.forename: Jin Mo
authors.initials: JM
authors.lastname: Goo
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: Lee
authors.forename: Chang Hyun
authors.initials: CH
authors.lastname: Kang
authors.forename: Young Whan
authors.initials: YW
authors.lastname: Kim
authors.forename: Jung Im
authors.initials: JI
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000556:secondary*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18