[A Case of Ischemic Colitis on the Anal Side of the Anastomosis Following Surgery for Descending Colon Cancer].

A 76-year-old man underwent laparoscopic partial resection of the descending colon for descending colon cancer. The common trunk of the left colic artery and the first branch of the sigmoid artery was ligated, while the inferior mesenteric artery(IMA)was preserved and the inferior mesenteric vein(IMV)was divided. The pathological diagnosis was pT3pN0M0, pStage ⅡA, and no adjuvant chemotherapy was administered. At 6 months postoperatively, CT showed inflammatory changes extending from the anastomosis to the rectum, but observation was continued as the patient was asymptomatic. At 8 months postoperatively, he developed abdominal pain and frequent defecation. Based on CT and endoscopic findings, ischemic colitis was diagnosed. Conservative treatment was ineffective, and a double-barrel ileostomy was performed. Although the inflammation improved postoperatively, progressive stenosis occurred, and 11 months after ileostomy, a high anterior resection including the anastomosis and stoma closure was performed. It was considered that preservation of the IMA and division of the IMV led to relatively increased venous congestion, resulting in delayed-onset ischemic colitis.