II. To determine the effect of the study drugs (aspirin [acetylsalicylic acid] + DFMO) and placebo with respect to proliferation (Ki67 labeling index), apoptosis (caspase-3 expression assay), and drug effect markers (COX-1, -2, polyamines, PGE2) from adenomas, aberrant crypt focus (ACF) and normal-appearing mucosa using pre- and 12-month post-intervention tissue biopsy samples.