Octreotide in Preventing or Reducing Diarrhea in Patients Receiving Chemoradiotherapy for Anal or Rectal Cancer

RATIONALE: Octreotide may be effective in preventing or controlling diarrhea in patients who are undergoing chemoradiotherapy for anal or rectal cancer. It is not yet known whether octreotide is effective in treating diarrhea. PURPOSE: This randomized phase III trial is studying octreotide in preventing or reducing diarrhea in patients who are undergoing chemoradiotherapy for anal or rectal cancer.

OBJECTIVES: Primary * Determine the ability of octreotide to prevent the incidence of moderate, severe, or life-threatening chemoradiotherapy-induced diarrhea (grades 2-4) in patients with anal or rectal cancer. Secondary * Compare the quality of life of patients treated with this drug vs placebo. * Compare the number of hospitalizations and use of antidiarrheal agents (e.g., Imodium®) related to diarrhea (or its complications) in patients treated with these drugs. * Compare treatment delays and/or dose reductions (chemotherapy and radiotherapy) in patients treated with these drugs. OUTLINE: This is a double-blind, placebo-controlled, randomized, multicenter study. Patients are stratified according to radiotherapy dose (\< 50 Gy vs ≥ 50 Gy), chemotherapy dose (bolus vs continuous), and gender. Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients receive octreotide\* intramuscularly (IM) 4-7 days before the start of chemoradiotherapy and on day 22 (± 3 days) during chemoradiotherapy. * Arm II: Patients receive placebo\* IM 4-7 days before the start of chemoradiotherapy and on day 22 (± 3 days) during chemoradiotherapy. NOTE: \*Patients receive a total of 2 injections of octreotide or placebo In both arms, treatment continues in the absence of unacceptable toxicity. Quality of life is assessed at baseline, at the completion of chemoradiotherapy, and at 3, 6, 9, and 15 months from the start of chemoradiotherapy. Patients are followed at 3, 6, 9, and 15 months from the start of chemoradiotherapy. PROJECTED ACCRUAL: A total of 226 patients (113 per treatment arm) will be accrued for this study within 2 years.