[Double and multiple carcinomas of the colon (author's transl)].

Double or multiple carcinomas of the colon represent approximately 4% of all colon carcinomas. They may arise spontaneously or occur as a result of some predisposing disease. It is necessary to distinguish between double or multiple carcinomas arising synchronously or in sequence. Diseases such as ulcerative colitis, colonic polyposis and adenomatous polyps are pre-disposing conditions whereas familial polyposis is pre-cancerous.