Frequency and significance of tumor thrombi in esophageal varices in hepatocellular carcinoma associated with cirrhosis.

Histological examination of the wall of the stomach and esophagus in patients with hepatocellular carcinoma associated with cirrhosis demonstrated intravariceal tumor thrombi in 13 (23.6%) of 55 cases studied. There were distant hematogenous metastases in 31 of them, of whom 12 (38.7%) had variceal tumor thrombi. Tumor thrombi were of varying sizes, and tumor cells appeared either intact, degenerated or necrotic. In seven cases, there was a firm adhesion of thrombi onto the vascular wall suggesting possible mural infiltration, but no extravascular metastases were noted grossly. These findings suggest a possibility of metastasis of hepatocellular carcinoma to the stomach and esophagus via the portal vein. It is also suggested that the degree of varices is not increased by tumor thrombus formation per se, and that both varices and tumor thrombi are due to extensive hepatofugal collateral circulation. Considering that 12 of 13 cases of intravariceal tumor thrombi had lung metastases, a portal vein-varices-lung route is possible for lung metastasis beside the established route through the hepatic vein in hepatocellular carcinoma.