Nonsurgical treatment of liver metastases.

Experimental studies demonstrate that angiotensin II and somatostatin analogues have some ability to redirect hepatic arterial blood flow toward liver metastases. Albumin microspheres and liposomes are both effective to animal models in enhancing intra-arterial drug delivery to tumor tissue. Clinical studies show that such strategies can also improve drug targeting in humans. Clinical trials of intrahepatic arterial chemotherapy demonstrate definite response and survival benefits, but toxicity can be considerable, and progression of extrahepatic disease remains an unsolved problem. Selective means of delivering radiation, biologic therapy, and thermal energy to liver metastases are possible alternative nonsurgical treatments that merit further investigation.