Invasive therapy of metastatic colorectal cancer to the liver.

Resection, when possible, is still the best hope for cure of colorectal metastasis to the liver. Poor prognostic indicators for survival include heavy tumor burden, the presence of extrahepatic disease, synchronous metastasis, and the inability to perform resection with a 1-cm margin. Questionable poor prognostic indicators include multiple metastases (more than three), bilobar disease, and the need to transfuse patients during resection. Preoperatively, a patient must be evaluated for the extent of liver disease and the presence of extrahepatic disease with a CT of the abdomen and routine studies of the chest. Intraoperatively, a surgeon should be able to perform or obtain ultrasonography of the liver to detect occult metastases and delineate anatomy. The surgeon should be experienced in wedge, segmental, and lobar resection. Equipment for cryotherapy and arterial infusion devices should be available, and staff experienced in these modalities should be present. If all of these factors are present, the options for the invasive treatment of colorectal metastasis to the liver can be carried out in a manner that should provide the most benefit at a low morbidity to this population of patients.