Regional Hepatic Chemotherapies in the Treatment of Colorectal Cancer Metastases to the Liver

The liver is the most common site of metastatic spread of colorectal cancer (CRC). Liver may be the only site of spread in as many as 30% to 40% of patients with advanced disease and can be treated with regional therapies directed toward their liver tumors. Surgery is currently the only potentially curative treatment, with a 5-year survival rate as high as 30% to 40% in selected patients. However, fewer than 25% of cases are candidates for curative resection. A number of other locoregional therapies, such as radiofrequency or microwave ablation, cryotherapy, and chemotherapy, may be offered to patients with unresectable but isolated liver metastases. However, for most patients with metastatic spread beyond the liver, systemic chemotherapy rather than regional therapy is a more appropriate option. We review the status of various regional hepatic chemotherapies in the treatment of colorectal metastases to the liver in the light of the available, published prospective, randomized trials; this discipline has not yet been properly applied to the burgeoning use of locally ablative techniques. The regional strategies reviewed include portal venous infusion (PVI) of 5-fluorouracil (5-FU), intra-arterial chemotherapy (hepatic arterial infusion [HAI]), chemoembolization, and selective internal radiation therapy (SIRT).