Establishment of an orthotopic tumour model for hepatocellular carcinoma and non-invasive in vivo tumour imaging by high resolution ultrasound in mice

Background/Aims In this study we established an orthotopic tumour model for hepatocellular carcinoma and evaluated a non-invasive high resolution ultrasound technique for diagnosis and follow-up of intrahepatic HCC. Methods Orthotopic liver tumours were induced by intrahepatic tumour cell injection of 105 Hepa129 hepatoma cells. Tumour establishment and growth were assessed by explorative laparotomy, ultrasound technique and hepatectomy one and two weeks after tumour cell implantation. Tumour establishment was confirmed histologically in liver sections. Results Our results show that the Hepa129 hepatoma cell line is suitable for orthotopic tumour establishment and that tumours can be diagnosed correctly by ultrasound imaging in all cases as confirmed by explorative laparotomy, hepatectomy and cross-sections. Tumour diameters obtained by explorative laparotomy correlated significantly with diameters assessed by ultrasound (r=0.7; P<0.0001). Tumour burden was slightly overestimated (1.2-fold) by ultrasound one week after tumour induction and relative tumour extensions increased 1.7-fold and 1.8-fold within one week as determined by subsequent explorative laparotomy or ultrasound imaging, respectively. Conclusions These data demonstrate in a systematic study that ultrasound imaging can be used as a reliable tool to detect and to follow up orthotopic liver tumours in this tumour model in mice.