A phase II pilot study was carried out on 30 patients to ascertain the toxicity and efficacy of combination chemotherapy with mitoxantrone, methotrexate, 5-fluorouracil (NMF) in the adjuvant setting for axillary lymph node-positive breast cancer. The NMF regimen was mitoxantrone 10 mg/m2, methotrexate 40 mg/m2, and 5-fluorouracil 600 mg/m2 administered i.v. on day 1, repeated every 3-4 weeks for 6 cycles. The median nadir WBC count was 2,000/microl; grade 4 leukocytopenia occurred only in 1 patient. Nausea and vomiting appeared as grade 0 and 1 severity in 26/30 patients. Alopecia was extremely mild, appeared as grade 0 and 1 in 29/30 patients. The overall and relapse-free survival rates were 67.8% and 68.4% at the 82-month follow-up, respectively. The overall survival rate in premenopausal patients was significantly better than that in postmenopausal patients (P<0.05). NMF is a well-tolerated combination regimen, suitable as adjuvant chemotherapy for node-positive breast cancer.