Question: An 88-year-old man was admitted to our hospital with the chief complaint of left flank pain. He had a history of ileocecal resection and sigmoidectomy for the treatment of colon cancer 7 years ago and has been treated for diabetes mellitus for >20 years. Laboratory findings showed a mild elevation of the white blood cell count (12,000/μL) and C-reactive protein (6.3 mg/dL), blood sugar (180 mg/dL), and hemoglobin A1c (8.9%) levels. No elevation of tumor marker levels was observed. Imaging studies showed an irregularly shaped, 70-mm tumor in the left side of the abdomen with an invasive growth pattern toward the abdominal wall and colon.