[A case of pathological complete response of advanced rectal cancer with liver metastasis accompanied by tumor thrombus following treatment with bevacizumab/FOLFOX4 chemotherapy].

A 58-year-old man underwent low anterior resection for type 2 rectal cancer with liver metastasis. An abdominal computed tomography (CT) scan showed multiple hepatic tumors (in S2, S3, S4, and S6) and a filling defect in the left portal vein. Pathological examination revealed a moderately differentiated adenocarcinoma, pSS, pN0, ly0, v3, with a tumor thrombus in the portal vein. After surgery, the patient was treated with combined chemotherapy of bevacizumab/Leucovorin and fluorouracil with oxaliplatin (FOLFOX4). After 11 courses of chemotherapy, tumor marker levels normalized, and the sizes of the liver metastases and thrombus in the left portal vein remarkably decreased. Resection of the left hepatic lobe and a partial resection of S6 were performed. Pathological examination revealed no residual cancer cells and indicated that the histological classification due to the chemotherapy regimen was Grade 3. The patient was alive for 5 years after the initial surgery, without recurrence.