Undifferentiated Pleomorphic Sarcoma of the Ascending Colon—A Case Report—

Abstract

A 79-year-old woman with right lower quadrant abdominal pain was admitted to our hospital. Abdominal contrast-enhanced computed tomography showed a 70-mm tumor in the ascending colon and peritoneal dissemination in the vicinity, with suspected invasion into the inferior leg of the duodenum. Colonoscopy showed a tumor of three-quarters of the circumference in the ascending colon, but a confirmed diagnosis was not obtained on biopsy. Right hemicolectomy with concomitant resection of the duodenum, jejuno-duodenal anastomosis, and resection of peritoneal dissemination were performed for the ascending colon tumor with peritoneal dissemination. Histopathological examination showed diffuse growth of short spindle-shaped cells with large heterozygous nuclei. On immunostaining, only vimentin was positive. The final diagnosis was undifferentiated pleomorphic sarcoma of the ascending colon. Computed tomography 3 months after surgery showed recurrent peritoneal dissemination. The patient died only 5 months after the initial operation. Undifferentiated pleomorphic sarcoma is prevalent in extremity soft tissues. Since undifferentiated pleomorphic sarcoma of the colon is rare, with only 27 cases, including the present patient, reported in the past, this case is reported along with a review of the relevant literature.