title: Integrated positron emission tomography and computed tomography in preoperative lymph node staging of non-small cell lung cancer.
abstract: BACKGROUND
  Integrated positron emission tomography and computed tomography (PET/CT) is increasingly used for the preoperative nodal staging of non-small cell lung cancer (NSCLC). The aim of this study was to evaluate the accuracy of PET/CT in comparison with CT in detection of nodal metastasis and preoperative nodal staging in patients with NSCLC, and to analyze the causes of the PET/CT false-negative and false-positive results.
  
  
  METHODS
  Consecutive patients with pathologically proven NSCLC who underwent staging using PET/CT from July 2008 to February 2012 were evaluated retrospectively. Nodal staging was pathologically confirmed on tissue specimens obtained at thoracotomy. The accuracy of PET/CT and CT in the assessment of intrathoracic nodal involvement was determined using histological results as the reference standard. Logistic regression was used to define the causes of the false-negative and false-positive results.
  
  
  RESULTS
  A total of 528 lymph node stations were evaluated in 101 patients. Lymph nodes were positive for malignancy in 43 out of 101 patients (42.6%), and 101 out of 528 nodal stations (19.2%). PET/CT was significantly more accurate for nodal staging than CT. The sensitivity, specificity, positive and negative predictive values, and accuracy of PET/CT for detecting nodal metastasis were 51.5%, 95.8%, 74.3%, 89.3%, and 87.3% and the corresponding data by CT were 45.5%, 87.1%, 45.5%, 87.1%, and 79.2%, respectively. PET/CT confers significantly higher specificity, positive predictive value, and accuracy than CT in detecting nodal metastasis. False-negative results by PET/CT are significantly associated with smaller lymph node size, whereas false-positive results are related to a combination of inflammatory disorders and larger lymph node size.
  
  
  CONCLUSIONS
  PET/CT confers significantly higher accuracy than CT in nodal staging, and is more specific and accurate than CT in detecting nodal metastasis but has a low sensitivity and high false-negative rate.
authors.affiliation: Department of General Internal Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Na
authors.initials: N
authors.lastname: Xu
authors.affiliation: Department of Respiratory Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Mengzhao
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Department of Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Yingqiang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of General Internal Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Jiao
authors.affiliation: Department of General Internal Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Weigang
authors.initials: W
authors.lastname: Fang
mesh_terms: D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology*; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009367:Neoplasm Staging / Q000379:methods*; D049268:Positron-Emission Tomography; D057234:Preoperative Period; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed