The action of floxuridine depends greatly on its concentration for treatment of liver metastases of colorectal carcinomas and other tumors. In isolated liver metastases it is best infused regionally in order to achieve a high concentration and to reduce systemic toxicity, particularly as it is almost entirely extracted by the liver. A totally implantable infusion pump has established itself as an effective, safe and reliable device of regional chemotherapy with floxuridine for palliative treatment of selected patients with metastases of colorectal carcinomas and other tumors. Life expectancy of patients with metastases of colorectal carcinomas was prolonged by 12-18 months when compared to a precedent control group without regional chemotherapy. This results require confirmation in a randomised phase III study. Patients with hepatocellular carcinoma can be treated with intraarterial doxorubicine and floxuridine infusions. Preliminary results are encouraging. The implantable system represents a major advance in drug administration, not only for the treatment of malignant disease but also a large number of other diseases. Continuous infusion of drugs using an implantable pump system will probably achieve greater importance in the future in the treatment of cancer.