[Successful treatment of advanced sigmoid colon cancer with liver metastases with cetuximab monotherapy as first-line treatment-a case report].

The prognosis for patients diagnosed with advanced colorectal cancer with liver metastases is poor. Chemotherapy should be administered with caution in such patients because of complications due to severe liver dysfunction. We report here the successful management of a case of advanced sigmoid colon cancer, with icterus due to severe liver metastases, treated with cetuximab as first-line therapy. A 72-year-old man presented at our institution with complaints of severe general fatigue, tarry stools, and abdominal distention. He was diagnosed with advanced sigmoid colon cancer with multiple liver metastases. Clinical examination revealed the presence of ascites. The patient had an Eastern Cooperative Oncology Group(ECOG) performance status(PS)score of 3. A biopsy specimen of the primary tumor showed well-moderately differentiated adenocarcinoma without KRAS mutation. He was diagnosed with advanced sigmoid colon cancer with multiple hepatic metastases. Cetuximab monotherapy was initiated as first-line treatment. After 4 courses of cetuximab monotherapy, results of laboratory tests showed an improvement, and a computed tomography(CT)scan revealed a regression in the size of the liver metastases. Because the results of liver function tests and the ECOG PS scores improved, we initiated combination chemotherapy with 5-fluorouracil, Leucovorin, oxaliplatin(FOLFOX), and cetuximab. This regimen was well tolerated up to 14 courses, during which the only adverse reaction reported was a rash of grade 2 toxicity. Thereafter, disease progression in the form of liver metastases resulted in a change in the combination therapy to irinotecan and S-1(IRIS)as second-line chemotherapy. Thereafter, irinotecan and panitumumab were administered as third-line therapy. The patient continued chemotherapy on an outpatient basis; however, he died due to disease progression 18 months after his first visit.