Standard treatment of metastatic colorectal cancers relies on fluoropyrimidines, irinotecan alone or in association with fluoropyrimidines, oxaliplatin in association with fluoropyrimidines, bevacizumab and anti EGFR antibodies. After failure of classical regimen the national reference frame on the basis of phase II study proposes an association of fluoropyrimidine and mitomycin. These treatments give response rates of 10-20% with progression free survivals from 2 to 3 months. Hepatic intra-arterial chemotherapy is logical in the case of isolated hepatic metastases nonaccessible to curative resection: 1) hepatic metastases are vascularized by hepatic arterial system in contrast to nontumoral hepatic parenchyma; 2) arterial perfusion of oxaliplatin leads to a strong extraction by the liver during the first passage, a high intra-tumoral concentration and a low systemic concentration. So oxaliplatin is a drug of choice for arterial treatment but combination with fluoropyrimidines is impossible because of need for prolonged perfusion. Floxuridin is not available in France. Raltitrexed, a definitive inhibitor of the thymidylate synthase, does not require a prolonged perfusion and could be a good substitute.In a previous pilot study we demonstrated the feasibility, safety and efficacy of combination of raltitrexed and oxaliplatin arterial perfusion. Now we propose a phase II randomized clinical trial to evaluate the efficacy of hepatic arterial infusion of raltitrexed and oxaliplatin association versus standard chemotherapy for patients with metastases of colorectal origin restricted to the liver after failure of conventional chemotherapy.