Small primary de novo adenocarcinoma of the colon with mesenteric lymphatic metastasis

It is felt that the majority of colorectal carcinomas develop by malignant degeneration of previously benign adenomatous polyps. A small primary colon carcinoma, thought to have developed de novo directly from the colonic mucosa without the usual polyp‐cancer sequence, is reported. This small nonulcerated lesion did not have the gross endoscopic appearance of a carcinoma and was associated with lymphatic metastasis. The need to include fiber‐optic colonoscopy as part of the routine preoperative work‐up and postoperative follow‐up to rule out synchronous and metachronous lesions not detected by barium contrast x‐ray studies is stressed.