[Regional growth preferences in hereditary, synchronous, and metachronous colorectal carcinomas. Basics of tumor surgery Part II].

This article discusses the therapeutic importance of the loss of self-regulation of cell division in polypoid adenomas and in the cloacogenic, cancerophilic rectal segment. Regional growth preferences can observed in familial adenomatous polyposis (FAP) and ulcerative colitis, as in other diseases featuring a cancerous disposition on the mucosa. For example, rectal carcinomas are more common than colon carcinomas if one considers the total mucosal surface area at risk. Malignant changes do not occur randomly in existing adenomas of FAP patients, and the adenomas' cell division--as in other adenomas--is governed by some degree of self-regulation. In FAP patients undergoing proctocolectomy, preferred new growth areas for carcinomas include the duodenum and ileum. In patients with synchronous colorectal cancers, the rectum is more commonly affected than other colon segments. If the rectum is resected, metachronous carcinomas are exceedingly rare in the remaining colon segments. Clinical decisions about rectal resection must be informed by understanding of the importance of this organ for anorectal continence as well as the described growth of colorectal malignancies.