The liver has a central role in human metabolism and represents one of the organ systems most often affected, especially by tumor diseases. The group of colorectal carcinomas metastatically almost exclusively attacks this organ, which, according to studies by Weiss and colleagues, can be attributed to venous drainage of the intestines through the portal vein. A large number of primary tumors often cause liver metastases as well as bone, lung, and brain metastases. After curative sanitation of the primary tumor, the liver infestation has a decisive influence on survival time of affected patients in many instances.