Macrogol 3350-based Oral Osmotic Laxative in Preventing Cancer in Patients at Risk of Colorectal Cancer

PRIMARY OBJECTIVES: I. To evaluate the effect of polyethylene glycol (PEG) 3350 (administered at 8 g or 17 g/day for six months) versus placebo on epidermal growth factor receptor (EGFR) expression. SECONDARY OBJECTIVES: I. To determine the effect of PEG 3350 on aberrant crypt foci (ACF) number and to compare the reduction in ACF number between the low dose (8 g PEG 3350/day) and higher dose (17 g PEG 3350/day) groups. II. To determine the effect of PEG 3350 on mucosal epithelial proliferation (marker of proliferation Ki-67 \[Ki-67\]). III. To determine the effect of PEG 3350 on mucosal apoptosis (cleaved caspase-3). IV. To determine the effect of PEG 3350 on snail family zinc finger 1 (SNAIL) protein expression. V. To determine the effect of PEG 3350 on messenger ribonucleic acid (mRNA) expression of SNAIL and EGFR. OUTLINE: Patients are randomized to 1 of 3 treatment arms. ARM A: Patients receive high-dose macrogol 3350-based oral osmotic laxative orally (PO) once daily (QD). ARM B: Patients receive low-dose macrogol 3350-based oral osmotic laxative PO QD. ARM C: Patients receive placebo (i.e., maltodextrose powder) PO QD. In all arms, treatment begins within 6-10 days after colonoscopy and continues for up to 6 months in the absence of unacceptable toxicity. After completion of study treatment, patients are followed at 30 days.