Study for investigating the effects of a probiotic on diarrhea caused by chemotherapy in patients with gastric, colon and rectum cancer

Primary objectives: The study investigates whether a Escherichia coli Nissle-suspenison has a (preventive) antidiarrheal effect in patients with tumors who are treated with chemotherapeutic schemes which are associated with increased occurances of diarrhea. Diarrhea caused by treatment are thought to be reduced in intensity and/or frequency by the treatment with Escherichia coli Nissle-Suspension. Primary endpoints: Common toxicity criteria (CTC) for diarrhea