The radiologic diagnosis and management of hepatic metastases.
The diagnosis of hepatic metastases is the responsibility of the diagnostic radiologist. In a comparison of the screening techniques, scintigraphy, sonography, and computed tomography, CT is the best single examination to determine the presence and extent of a hepatic mass. Hepatic angiography is now reserved for problem solving and in preparation for therapeutic management. Superselective catheterization is imperative and can be accomplished in 95%. Transcatheter management by hepatic artery infusion and embolization is feasible because the blood supply to hepatic metastases originates almost exclusively from the hepatic artery (90-95%), while the normal liver parenchyma has a dual supply--hepatic artery (25%) and portal vein (75%). This treatment delivered to the hepatic artery selectively effects the neoplasm. In the event of multiple hepatic (45%) arteries, occlusion of the aberrant artery with a steel coil redistributes flow through a single artery to facilitate infusion. The median survival from the time of the initiation of hepatic artery infusion for the treatment of metastatic colorectal carcinoma is 8 months and 15 months when the infusion is associated with occlusion. The median survival of 11.5 months is observed from the time of hepatic artery embolization which usually is done after failure of all other therapeutic modalities.