In vivo microscopy of hepatic tumors in animal models: a dynamic investigation of blood supply to hepatic metastases.

The dynamics of blood circulation in three experimental animal models of hepatic metastasis were investigated with in vivo microscopy. It was demonstrated that the tumor vasculature communicated with the portal venules and hepatic sinusoids that surrounded the tumors. The hepatic artery was not seen to connect to the tumors directly. However, it was demonstrated that arterial blood entered tumors through the portal venules and that the hepatic arterial flow entered the tumor without resistance, while blood from the portal vein met great resistance at the tumor border, with only small amounts entering the tumor. Interruption of either the hepatic artery or the portal vein did not result in cessation of the blood circulation in hepatic tumors. A reciprocal relationship between the hepatic arterial and portal venous supplies to hepatic tumors was suggested, and it was hypothesized that arterioportal communications play an important role in the arterial and portal venous supply of blood to hepatic tumors. A comprehensive understanding of the blood supply of hepatic tumors is important for improving clinical treatment of hepatic tumors.