Multiple Colon Neoplasms:  Prognostic and Therapeutic Implications

It is becoming clear that a bowel which undergoes frequent polypoid changes, either adenomatous or villous, is more prone to develop a malignant neoplasm. Likewise, a bowel which has produced one carcinomatous lesion has a much greater probability of developing a second such lesion. From a large cancer detection center, Rider et al¹ reported the incidence of carcinoma of the large bowel as 2.1% in patients undergoing routine gastrointestinal examinations. The incidence of cancer in a bowel containing polyps increases sharply. Patients with a single polyp were found to have a 7% to 11% chance of developing a colonic carcinoma, whereas in patients with multiple colonic polyps the incidence of cancer increased to 18% to 21%.^1-3

A recent review of 1,084 cases of carcinoma of the colon and rectum at the Hospital of the University of Pennsylvania allowed a further evaluation of the relationship between polyps and cancer, as