Stimulation of haematogenous liver metastases by ischaemia‐reperfusion in rats

Objective: To find out whether hepatic ischaemia‐reperfusion stimulates hepatic tumour metastases using a cell line of rat ascitic hepatoma (AH130). Design: Prospective experimental study. Setting: University laboratories, Japan. Materials: 118 male Donryu rats. Intervention: After laparotomy alone (group 1, n = 35) or laparotomy and 20‐minutes ischaemia (group 2, n = 34) or laparotomy and 30‐minutes ischaemia (group 3, n = 34) of the median and left hepatic lobes, the animals were given either an intraportal injection of 1 × 10 5 or an intravenous injection of 1 × 10 6 viable AH130 cells. Main outcome measures: 10 days after inoculation of tumour cells the number of nodules on the surface of the right lobe and of the median plus left lobes were separately counted for each liver. Results: Irrespective of the route of tumour inoculation in group 1, there was no significant difference in the number of tumours/g liver between the right and the median plus left lobes. However, in groups 2 and 3, the number of tumours/g liver in the median plus left lobes was significantly higher than in the right lobe ( p < 0.05). Furthermore, in the median plus left lobes, animals who had had 30 minutes of ischaemia had significantly more tumours than those in the other two groups ( p < 0.01). Conclusion: Hepatic ischaemia‐reperfusion may increase the risk of development of haematogenous liver metastases, by stimulating tumour cell‐endothelial cell interactions. Copyright © 1999 Taylor and Francis Ltd.