title: [Value of quantitative iodine-based material decomposition images with gemstone spectral CT imaging in the follow-up of patients with hepatocellular carcinoma after TACE treatment].
abstract: OBJECTIVE
  To investigate the value of quantitative iodine-based material decomposition images with gemstone spectral CT imaging in the follow-up of patients with hepatocellular carcinoma (HCC) after transcatheter arterial chemoebolization (TACE).
  
  
  METHODS
  Consecutive 32 HCC patients with previous TACE treatment were included in this study. For the follow-up, arterial phase (AP) and venous phase (VP) dual-phase CT scans were performed with a single-source dual-energy CT scanner (Discovery CT 750HD, GE Healthcare). Iodine concentrations were derived from iodine-based material-decomposition images in the liver parenchyma, tumors and coagulation necrosis (CN) areas. The iodine concentration difference (ICD) between the arterial-phase (AP) and venal-phase (VP) were quantitatively evaluated in different tissues.The lesion-to-normal parenchyma iodine concentration ratio (LNR) was calculated. ROC analysis was performed for the qualitative evaluation, and the area under ROC (Az) was calculated to represent the diagnostic ability of ICD and LNR.
  
  
  RESULTS
  In all the 32 HCC patients, the region of interesting (ROI) for iodine concentrations included liver parenchyma (n=42), tumors (n=28) and coagulation necrosis (n=24). During the AP the iodine concentration of CNs (median value 0.088 µg/mm(3)) appeared significantly higher than that of the tumors (0.064 µg/mm(3), P=0.022) and liver parenchyma (0.048 µg/mm(3), P=0.005). But it showed no significant difference between liver parenchyma and tumors (P=0.454). During the VP the iodine concentration in hepatic parenchyma (median value 0.181 µg/mm(3)) was significantly higher than that in CNs (0.140 µg/mm(3), P=0.042). There was no significant difference between liver parenchyma and tumors, CNs and tumors (both P>0.05). The median value of ICD in CNs was 0.006 µg/mm(3), significantly lower than that of the HCC (0.201 µg/mm(3), P<0.001) and hepatic parenchyma (0.117 µg/mm(3), P<0.001). The ICDs in tumors and hepatic parenchyma showed no significant difference (P=0.829). During the AP, the LNR had no significant difference between CNs and tumors (a median value 1.805 vs. 1.310, P=0.389), and during the VP, the difference was also non-significant (the median value 0.647 vs. 0.713, P=0.660). The mean Az value of ICDs for evaluation of surviving tumor tissues was 0.804, whiles LNR measured a disappointing result in both AV images and VP images.
  
  
  CONCLUSIONS
  Quantitative iodine-based material decomposition images with gemstone spectral CT imaging can improve the diagnostic efficacy of CT imaging for HCC patients after TACE treatment.
authors.affiliation: Department of Diagnostic Imaging, Cancer Institute and Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100021, China.
authors.forename: Gusheng
authors.initials: G
authors.lastname: Xing
authors.affiliation: Department of Diagnostic Imaging, Cancer Institute and Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100021, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Diagnostic Imaging, Cancer Institute and Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100021, China.
authors.forename: Chenrui
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Diagnostic Imaging, Cancer Institute and Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100021, China.
authors.forename: Xinming
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Department of Diagnostic Imaging, Cancer Institute and Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100021, China; Email: cjr.zhouchunwu@vip.163.com.
authors.forename: Chunwu
authors.initials: C
authors.lastname: Zhou
mesh_terms: D001158:Arteries; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000628:therapy; D004621:Embolization, Therapeutic; D005500:Follow-Up Studies; D006801:Humans; D007454:Iodides; D007455:Iodine; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000628:therapy; D012372:ROC Curve; D014057:Tomography, X-Ray Computed
chemical_list: D007454:Iodides; D007455:Iodine