Adenomatous and carcinomatous changes within hyperplastic colonic epithelium.

Hyperplastic colonic polyps are benign, nonneoplastic proliferations; unlike tubular and villous adenomas, they do not predispose the patient to colonic cancer. Theoretically, these hyperplastic polyps, like normal colonic epithelium, should be able to undergo adenomatous transformation and possibly develop into cancer. In this report, we discuss an unusual case of a patient with numerous hyperplastic polyps, in which adenomatous changes occurred and cancer developed. We also discuss the significance of these changes as they relate to the polyp-cancer sequence.