[A case of five cancerous lesions of the colon diagnosed by preoperative examination].

A rare case of five synchronous colon cancers has been reported. A 52-year-old woman was admitted to our hospital complaining of pain at the right lower quadrant. roentgenographic and endoscopic studies of the colon revealed three cancerous lesions in the cecum the ascending colon, and two lesions at the sigmoid and rectosigmoid colon. Histopathological findings of the respective specimens showed one advanced cancer which had invaded into the muscuralis propria on the upper part of the Bauhin's valve, and four early type carcinomas invaded into the mucosa or submucosa. There were metastatic lesions at the regional lymph nodes in sigma, but distant metastatic lesions were not observed. These histologic findings suggest that these carcinomas had not arisen in preexisting benign adenomas, but had arose from normal mucosa (de novo cancer).