Curative resection after a response to treatment with mFOLFOX6 for unresectable sigmoid colon cancer: Report of a case

Abstract

We herein report a case of curative resection, after a response to chemotherapy with mFOLFOX6, for sigmoid colon cancer which had been unresectable due to an invasion of the primary lesion into the aorta. A 58-year-old male patient visited the department of internal medicine of our hospital with chief complaints of lower abdominal pain and a lower abdominal mass. Computed tomography suggested colorectal cancer, and the patient was referred to our department. A diagnosis of sigmoid colon cancer was made, and a laparotomy was performed. However, the cancer was unresectable due to its invasion into the aorta, which led to the implementation of sigmoid-rectal anastomosis. Thereafter, chemotherapy with mFOLFOX6 was initiated, and the tumor shrunk markedly after seven courses of the treatment. The clinical response was rated as partial response. Radical resection of the tumor was considered possible, and another laparotomy was performed. The tumor had shrunk markedly, and a separation of the tumor from the aorta was possible. Therefore, sigmoid colectomy was conducted followed by a D3 lymph node dissection. The overall findings were type 5, pSS, ly0, v0, pN0 (0/26), sH0, sP0, cM0, fStage II, PM0, DM0, RM0, and CurA. In the present study, mFOLFOX6 as neoadjuvant chemotherapy for colon cancer was found to be effective.