Patients with measurable liver metastases due to breast cancer and elevated liver enzymes were enrolled into the study. The planned schedule was mitomycin C 8 mg/m2 on day 1, 5-fluorouracil 750 mg/m2 and folinic acid 300 mg/m2 on day 1 and 2 every 4 weeks (Mi-Fu-Fo). Between May 1998 and December 2002, 30 patients with a median age of 51 years (range 33-74) were enrolled. All of them suffered from extensive metastases of the liver resulting in liver dysfunction. Myelosuppression was the most frequent toxicity. Six patients had a partial remission, 12 patients had stable disease and 12 patients progressed during treatment. The median time to progression was 4.5 months in all patients and 7.0 months in patients who responded to the therapy. The median overall survival for the total population was 6.0 months and in the group of responding patients 12.0 months. Mi-Fu-Fo, therefore, provides a valid option for breast cancer patients with liver dysfunction due to liver metastases.