Changes in hepatic haemodynamics in rats with overt liver tumour.

Overt liver tumour was induced in Fisher rats by intraportal administration of 1.6 x 10(7) Walker carcinosarcoma cells. Control groups of rats received similar volumes of dead cells or saline intraportally. All animals were studied at 3 weeks when overt tumour was present. The Hepatic Perfusion Index (HPI) was significantly raised in rats with overt tumour compared to both groups of control animals. Portal flow and portal venous inflow were significantly reduced in the presence of overt tumour but hepatic arterial flow did not alter. These observations suggest that the alteration in the HPI in the presence of overt tumour results from an alteration in portal venous flow and inflow even though the blood supply to the tumour is principally derived from the hepatic artery. The changes in hepatic haemodynamics in the presence of tumour were accompanied by a reduction in portal pressure, an increase in splanchnic vascular resistance and an increase in the degree of arteriovenous shunting through the liver. Portal vascular resistance was unchanged. These findings indicate that the presence of overt hepatic tumour results in gross derangements of hepatic blood flow. These changes must be taken into consideration when attempting to potentiate the delivery of cytotoxic drugs to hepatic tumour by manipulation of hepatic haemodynamics.