[Multiple hepatic metastases from colon cancer successfully treated with irinotecan and S-1 plus panitumumab as second-line therapy-a case report].

: The patient was a 55-year-old man who had been diagnosed as having liver metastases (S3, S4, S5, S6, and S7) from sigmoid colon cancer in March 2010. In June 2010, he underwent sigmoid colon cancer resection, followed by local ablation therapy for the liver tumors( S4, S5, and S6) and hepatic segmentectomy( S3 and S7). Subsequently, adjuvant chemotherapy with S-1 and oxaliplatin( SOX) was initiated. After 6 courses, hepatic metastasis from colon cancer recurred. Thus, primary treatment with SOX plus bevacizumab for advanced metastatic colorectal cancer was initiated. However, progressive disease was diagnosed after 10 postoperative courses of chemotherapy, and therefore, chemotherapy with irinotecan and S-1 (IRIS) plus panitumumab was initiated as secondary treatment. Tumor marker levels reduced with this treatment, and diagnostic imaging indicated a partial response. We report herein a case of a patient who was successfully treated with IRIS plus panitumumab. This therapeutic regimen is useful as second-line treatment because it has the advantage of not requiring a pump for administration and treatment can be tailored to an individual patient's condition, for example, according to pathology and the patient's lifestyle needs.