title: Incremental value of PET/CT Over CT for mediastinal nodal staging of non-small cell lung cancer: Comparison between patients with and without idiopathic pulmonary fibrosis.
abstract: OBJECTIVE
  We aimed to compare the incremental value of FDG PET/CT over CT for the assessment of mediastinal nodal status between patients with non-small cell lung cancer (NSCLC) and idiopathic pulmonary fibrosis (IPF) and those with NSCLC but without IPF.
  
  
  METHODS
  Forty-two patients with NSCLC and IPF (mean age, 66 years) were matched to 168 patients with NSCLC but without IPF (mean age, 65 years). Patients underwent surgical mediastinal nodal staging after both integrated PET/CT and contrast-enhanced CT scans had been obtained. Histopathologic nodal assessment served as the reference standard.
  
  
  RESULTS
  PET/CT had better specificity (91% [29/32 patients] vs 47% [15/32]; p = 0.0002) and accuracy (83% [35/42] vs 50% [21/42]; p = 0.001) than CT did in patients with IPF. In patients without IPF, PET/CT was better than CT alone with regard to sensitivity (62% [26/42] vs 40% [17/42]; p = 0.0067), specificity (96% [121/126] vs 84% [106/126]; p = 0.0002), and accuracy (88% [147/168] vs 73% [123/168]; p < 0.0001). Thus, the incremental accuracy of PET/CT, which was 33% (14/42) for patients with IPF and 14% (24/168) for patients without IPF (p = 0.0041), was mainly the result of improved specificity.
  
  
  CONCLUSIONS
  PET/CT offers significantly increased accuracy versus CT in mediastinal nodal staging in patients with NSCLC and IPF compared with patients with NSCLC but without IPF, mainly because of improved specificity.
authors.affiliation: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Gangnam-gu, Seoul, Republic of Korea.
authors.forename: Tae Yeon
authors.initials: TY
authors.lastname: Jeon
authors.forename: Kyung Soo
authors.initials: KS
authors.lastname: Lee
authors.forename: Chin A
authors.initials: CA
authors.lastname: Yi
authors.forename: Man Pyo
authors.initials: MP
authors.lastname: Chung
authors.forename: O Jung
authors.initials: OJ
authors.lastname: Kwon
authors.forename: Byung-Tae
authors.initials: BT
authors.lastname: Kim
authors.forename: Young Mog
authors.initials: YM
authors.lastname: Shim
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications / Q000175:diagnosis*; D008297:Male; D008479:Mediastinal Neoplasms / Q000150:complications / Q000175:diagnosis*; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods*; D011658:Pulmonary Fibrosis / Q000150:complications / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods*