Growth Characteristics and Imaging Properties of the Morris Hepatoma 3924A in ACI Rats: A Suitable Model for Transarterial Chemoembolization

Purpose: For experimental studies investigating modalities and efficacy of transarterial chemoembolization (TACE) in hepatocellular carcinoma (HCC) an animal model resembling the human situation as closely as possible would be appropriate. Specifically, reproducible tumor growth characteristics with the capability for appropriate in vivo imaging to monitor treatment efficacy are required.Methods: Morris hepatoma 3924A was implanted into the liver of 30 ACI rats. Tumor growth was followed by angiography (n = 10), ultrasound (US, n = 30), native computed tomography (CT, n = 16), and native magnetic resonance imaging (MRI, n = 30) between day 8 and day 36 after implantation. The radiological morphological characteristics were compared with the macroscopic and microscopic histological findings of the explanted tumors.Results: In all 30 animals a solitary liver tumor was found and macroscopically no signs of metastases, ascites, or peritoneal tumor were visible. On histopathological examination tumor sizes ranged between 27 ± 3 mm3 (day 8) and 3468 ± 79 mm3 (day 36). The first signs of tumor necrosis occurred at day 16. US allowed tumor visualization from day 8, MRI from day 8, angiography from day 10, and CT from day 14.Conclusions: The tumor model has the potential to be used for the visualization of tumor growth by MRI and US. The potential for monitoring therapeutic effects of TACE needs to be investigated