Sixty chemotherapy-naive breast cancer patients of 30 to 71 years in age, P.S. = 0-1, receiving 5-fluorouracil-epirubicin-cyclophosphamide (FEC 75) q 21 days or cyclophosphamide-methotrexate-5-fluorouracil (CMF) or 120 mg/m2 epirubicin or high dose mitomycin-methotrexate-mitoxantrone (MMM) q 14 days (+ G-CSF) or 100 mg/m2 epirubicin (+ G-CSF) were randomized to receive, 15 min before chemotherapy, 8 mg i.v. bolus of ondansetron or 3 mg i.v. granisetron or 5 mg i.v. tropisetron and no further antiemetic therapy in the following days.