[A case of unresectable multiple hepatic metastases from colorectal cancer successfully treated with panitumumab therapy on third-line].

: In a patient with multiple liver metastases of colorectal cancer in whom tumor response had been achieved by 5-FU hepatic arterial infusion, the catheter for arterial infusion chemotherapy was occluded resulting in re-elevation of tumor marker levels. Second-line IRIS therapy using S-1 and CPT-11 was started. IRIS therapy reduced tumor marker levels to a degree greater than that previously achieved with 5-FU hepatic arterial infusion, and diagnostic imaging allowed a judgment of partial response. But tumor marker levels increased gradually. After all, diagnostic imaging allowed a judgment of progressive disease and an eminent elevation of tumor marker levels in one year. Third-line panitumumab therapy was started. Panitumumab therapy reduced tumor marker levels to a degree greater than that previously achieved with 5-FU hepatic arterial infusion and IRIS therapy, and diagnostic imaging allowed a judgment of partial response. We report herein a successful case. Hepatic arterial infusion therapy is one of the treatment methods characterized by a lower incidence of adverse reactions, relatively low cost, and expectation of high anti-tumor efficacy as compared to chemotherapy such as FOLFIRI. IRIS therapy does not require a port insertion and pump carrying, and its cost is about half of FOLFIRI therapy. When used as second-line therapy for unresectable colorectal cancer, non-inferiority of IRIS therapy to FOLFIRI therapy has been demonstrated in a phase II/III clinica (l FIRIS) study. We may say that IRIS therapy is promising as an equivalent to hepatic arterial infusion therapy in the treatment of liver metastases of colorectal cancer. In addition, we may say that panitumumab therapy is promising as an equivalent to hepatic arterial infusion therapy and IRIS therapy.