A Case of Metastasis of Ascending Colon Cancer to the Small Intestine That Was Diagnosed Based on Ileus

: A 69-year-old man was administered an ileus tube for ileus by ascending colon cancer. The next day, he underwent right hemicolectomy with D3 lymph node dissection for perforative peritonitis due to ascending colon cancer. The pathological diagnosis was A, type 2, muc>tub1, pT3, pN0. M0, pStageⅡ. He received 5 courses of UFT/Leucovorin(LV)chemotherapy. Two years later, he was hospitalized for ileus. He underwent surgery. The peritoneal dissemination was absent in the surgical findings. We resected a small intestinal tumor from the oral side of anastomosis. Because the tumor appearance and pathological findings were similar to those of ascending colon cancer, the patient was diagnosed with metastasis of ascending colon cancer to the small intestine. We report our rare encounter with metastases of colorectal cancer to the small intestine.