[Panitumumab as third-line chemotherapy shrank unresectable multiple liver metastases from rectal cancer, making them resectable - report of a case].

We report a case of unresectable multiple liver metastases, in which there was such a good response to panitumumab as third-line chemotherapy, that they were converted into resectable metastases. A 67-year-old man was admitted to our department for rectal cancer with synchronous unresectable multiple liver metastases. After the primary lesion was resected, modified FOLFOX6 regimen was started as first-line chemotherapy. After 10 courses of FOLFOX6 followed by 14 courses of sLV5FU2 regimen, the liver metastases became smaller and were thought to be resectable. Before hepatectomy, we performed portal vein embolization to enlarge the remnant liver, but the tumor grew larger again and we had to cancel the operation. Then, the second-line chemotherapy with FOLFIRI regimen failed. As third-line chemotherapy, panitumumab alone was administered to him and the tumor greatly shrank after 5 courses. We were able to resect the liver metastases with extended right posterior segmentectomy and partial resection. He has been well without recurrence for one year since hepatectomy. This case is rare in that panitumumab alone as third-line chemotherapy shrank unresectable liver metastases and made them resectable. The result is highly suggestive for management, including chemotherapy and operation of multiple liver metastases from colorectal cancer.