title: An implantable rat liver tumor model for experimental transarterial chemoembolization therapy and its imaging features.
abstract: OBJECTIVE
  To establish an ideal implantable rat liver tumor model for interventional therapy study and examine its angiographic signs and MRI, CT features before and after embolization.
  
  
  METHODS
  Forty male Wistar rats were implanted with Walker-256 tumor in the left lateral lobe of liver. Digital subtraction angiography (DSA) and transarterial chemoembolization were performed on day 14 after implantation. Native computer tomography (CT, n=8) and native magnetic resonance (MR, n=40) were performed between the day 8 and day 21 after implantation. The radiological morphological characteristics were correlated with histological findings.
  
  
  RESULTS
  Successful implantation was achieved in all forty rats, which was confirmed by CT and MRI. MR allowed tumor visualization from day 8 while CT from day 11 after implantation. The tumors were hypodensity on CT, hypointense on MR T1-weighted and hyperintense on T2-weighted. The model closely resembled human hepatocarcinoma in growth pattern and the lesions were rich in vasculature on angiography and got its filling mainly from the hepatic artery. Before therapy, tumor size was 211.9+/-48.7 mm(3). No ascites, satellite liver nodules or lung metastasis were found. One week after therapy, tumor size was 963.6+/-214.8 mm(3) in the control group and 356.5+/-78.4mm(3) in TACE group. Ascites (4/40), satellite liver nodules (7/40) or lung metastasis (3/40) could be seen on day 21.
  
  
  CONCLUSIONS
  Walker-256 tumor rat model is suitable for the interventional experiment. CT and MRI are helpful in animal optioning and evaluating experimental results.
authors.affiliation: Department of Interventional Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei Province, China. wxyao2001@yahoo.com.cn
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Chuan-Sheng
authors.initials: CS
authors.lastname: Zheng
authors.forename: Gan-Sheng
authors.initials: GS
authors.lastname: Feng
authors.forename: Chen-Kai
authors.initials: CK
authors.lastname: Zhuo
authors.forename: Jun-Gong
authors.initials: JG
authors.lastname: Zhao
authors.forename: Xi
authors.initials: X
authors.lastname: Liu
mesh_terms: D000818:Animals; D002279:Carcinoma 256, Walker / Q000473:pathology / Q000628:therapy*; D016461:Chemoembolization, Therapeutic; D004195:Disease Models, Animal; D006499:Hepatic Artery; D008113:Liver Neoplasms / Q000473:pathology / Q000628:therapy*; D008279:Magnetic Resonance Imaging; D008297:Male; D009368:Neoplasm Transplantation; D051381:Rats; D017208:Rats, Wistar; D014407:Tumor Cells, Cultured