Hematogenous intestinal metastases from sigmoid colon cancer presenting as iliopsoas abscess and bowel obstruction

Intestinal metastases from colorectal cancer typically occur by intraperitoneal spread, whereas those occurring via hematogenous route are exceedingly rare. We report a case of intestinal metastases from sigmoid colon cancer that presented as iliopsoas abscess and ileus. A 78-year-old man who had undergone sigmoidectomy for sigmoid colon cancer 5 years ago was referred to our hospital with recurrent ileus and fever. Abdominal computed tomography showed a left iliopsoas abscess and a mass near the abscess that had ostensibly caused ileus. The patient underwent segmental resection of the jejunum including the mass. Histopathological examination of the resected specimen revealed moderately differentiated adenocarcinoma proliferating mainly in the submucosal and muscular layers, which was pathologically identical to the colon cancer resected 5 years ago. He died 18 months after the surgery because of liver metastases. This case report highlights the delayed occurrence of colorectal metastases at unusual sites, such as the small bowel, more than 5 years after the resection of the primary cancer. Intestinal metastases should be considered in patients with a history of colon cancer, particularly in those with recurrent ileus or abdominal abscess with no obvious cause.