Patterns of spontaneous metastasis of transplantable hepatocellular carcinomas.

A number of transplantable rat hepatocellular carcinomas of varied phenotype were examined for their ability to metastasize. A striking diversity of pattern was observed, ranging from presentation in almost every organ to none at all. No relationship between metastatic capability and growth rate, tumor size, chromosome composition, or other functional characteristics was noted. Interestingly, several of the tumors demonstrated a lymphatic to vascular route of spread, very similar to that of human tumors.