Hepatic artery chemotherapy: the relative importance of direct organ distribution vs. the constant-infusion schedule

Ten patients with colorectal cancer metastatic to the liver were treated with hepatic arterial infusion (HAI) chemotherapy as second-line treatment following relapse after systemic venous infusion (SVI) of 5-fluorouracil. The objective was to determine if direct regional drug infusion would obviate drug resistance as has been reported when first-line treatment with 5-Fu was delivered by bolus schedule. The response rate to SVI as first-line treatment was 60% (6/10 patients) and only two patients responded to HAI; both had achieved an ongoing response to SVI. A tenuous interpretation of this experience is that the constant infusion schedule is the essential component to HAI chemotherapy in that none of the eight patients with established resistance to the infusion schedule responded to arterial infusion. However, prospective comparative trials will be necessary to establish the point. The advantages of SVI in comparison to HAI include the ability to treat extrahepatic disease as well as patients with aberrant or anomalous hepatic vasculature. In addition, the cost and complications of SVI are substantially less than that of HAI. A major question is the issue of the contribution of either treatment to meaningful survival.