[A Case of Double Colorectal Cancer Diagnosed by Preoperative CT Colonography].

A 66‒year‒old man was admitted to our hospital because of anemia and a positive fecal occult blood test in the medical examination. Colonoscopy revealed a type 2 advanced sigmoid colon cancer with circular stenosis. Computed tomography (CT)colonography was performed to examine the oral colon. The apple core signs were found both in the sigmoid and transverse colon. We diagnosed a double colon cancer and performed a laparoscopic left hemicolectomy and sigmoidectomy. The tumor was histopathologically diagnosed as a multiple cancer including a transverse and a sigmoid colon cancer. Although evaluations of the intestine for colon cancer with stenosis are performed by enema examination or endoscopic examination after colon stent placement, both examinations are invasive. CT colonography is considered to be a minimally invasive and an effective preoperative examination for colorectal cancer with stenosis.