title: Iodine quantification to characterize primary lesions, metastatic and non-metastatic lymph nodes in lung cancers by dual energy computed tomography: An initial experience.
abstract: OBJECTIVE
  To investigate whether dual energy computed tomography (CT) with iodine quantification can characterize primary lesions and metastatic lymph nodes from non-metastatic ones in non-small cell lung cancer (NSCLC).
  
  
  METHODS
  Sixty-one patients with NSCLC confirmed by pathology underwent chest contrast CT scan with dual energy computed tomography before surgery. The Iodine concentration (IC) and normalized iodine concentration (NIC) values of the primary lesions, 20 metastatic and 20 non-metastatic lymph nodes were measured, respectively. The differences between the primary lesions, metastatic and non-metastatic lymph nodes were statistically analyzed.
  
  
  RESULTS
  For the IC and NIC values of the primary lesions and their metastatic lymph nodes, there were no significant differences between lung squamous cell carcinomas and adenocarcinomas, respectively (P>0.05), while significant differences existed between metastatic and non-metastatic lymph nodes, respectively (P<0.05). The IC of 29.32 100μg/cm(3) and NIC value of 0.4328 of a lymph node represented the optimal threshold to discriminate metastatic from non-metastatic lymph nodes and yielded the following: sensitivity, 80% and 75%; specificity, 65% and 75%; PPV, 70% and 75%; NPV, 76% and 75%; accuracy, 73% and 75%, respectively.
  
  
  CONCLUSIONS
  Although its value in distinguishing primary lesions and their metastatic lymph nodes in NSCLC needs to be verified in further studies, dual energy CT with iodine quantification may be used to differentiate metastatic from non-metastatic lymph nodes in NSCLC.
authors.affiliation: Department of Radiology, Tianjin Medical University Cancer Institute and Hospital; National Clinical Research Center for Cancer; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Huan-hu-xi Road, Hexi District, Tianjin 300060, China. Electronic address: lixb@bjmu.edu.cn.
authors.forename: Xubin
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Radiology, Tianjin Medical University Cancer Institute and Hospital; National Clinical Research Center for Cancer; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Huan-hu-xi Road, Hexi District, Tianjin 300060, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Meng
authors.affiliation: Department of Radiology, Tianjin Medical University Cancer Institute and Hospital; National Clinical Research Center for Cancer; Key Laboratory of Cancer Prevention and Therapy, Tianjin; Huan-hu-xi Road, Hexi District, Tianjin 300060, China.
authors.forename: Zhaoxiang
authors.initials: Z
authors.lastname: Ye
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D003287:Contrast Media / Q000493:pharmacokinetics; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007455:Iodine / Q000493:pharmacokinetics*; D007472:Iohexol; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement; D015900:Radiography, Dual-Energy Scanned Projection; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; D007455:Iodine
keywords: Computed tomography; Differential diagnosis; Dual energy; Lung cancer