The patient was a 52-year-old woman who had sigmoid colon cancer with liver metastasis and multiple lung metastases. Resection of curability B was performed, and alternating adjuvant chemotherapy consisting of hepatic artery injection of 5-FU and systemic administration of CPT-11 was performed. Lung recurrence was found and no antitumor effect of chemotherapy was observed, so the CPT-11 which had been administered every other week was given every week in a dose of 60 mg/body, half of the original dose. Moreover, 5'-DFUR was administered in a dose of 800 mg/day every day. As a result, lung metastasis tumors were reduced markedly. Adverse events such as nausea, vomiting and depilation were mitigated, and no other toxicity was observed. The patient could thus be treated extremely safely in the outpatient clinic. This was considered to be a valuable case suggestive of the significance of combination chemotherapy of CPT-11 and 5'-DFUR and the importance of appropriate administration of CPT-11.