Phase III Double-Blind Study of Glutamine Versus Placebo in the Prevention of Acute Diarrhea in Patients Receiving Pelvic Radiation Therapy

OBJECTIVES: I. Determine whether glutamine is effective in reducing the acute treatment related diarrhea in patients receiving pelvic external beam radiation therapy as adjuvant or primary treatment of malignancy. II. Determine whether glutamine can reduce chronic treatment related enteropathy following completion of therapy. III. Determine whether glutamine causes any toxicity in this situation. IV. Provide initial reliability and validity data for a patient bowel function questionnaire.

OUTLINE: This is a randomized, double-blind, placebo controlled study. Patients are stratified by history of anterior resection of the rectum (yes vs no); total planned cumulative dose, including boost fields of external beam radiotherapy (4500-5350 cGy vs 5350-6000 cGy vs greater than 6000 cGy); use of fluorouracil (none vs bolus vs continuous infusion); and primary site (rectal cancer vs prostate cancer vs gynecological cancer vs other). Beginning the first or second day of radiotherapy, patients receive either oral glutamine or a placebo twice daily, including the days that they do not receive radiotherapy. Patients continue on treatment throughout radiotherapy and continue 2 weeks postradiotherapy or until grade 3 diarrhea occurs. Patients are followed weekly for 4 weeks, then at 12 months, and then at 24 months after radiotherapy.