Thirty-nine patients with brain metastasis from breast cancer who were treated in our hospital between 1978 and 1992 and followed up until November 1995 were reviewed. The initial diagnosis of brain metastasis and follow-up were made by MRI and/or CT. Extracranial metastases were found in 90% of the patients and were the cause of death in 89%. Treatments included surgery alone in 2 patients (group S) surgery plus postoperative radiotherapy in 8 (group SR), radiotherapy alone in 28 (group R) and conservative therapy in 1 (group C). Radiotherapy of up to 40Gy to the whole brain was carried out, but was performed in only 75% of patients in group R. The overall median survival was 5.4 months with a 1-year survival rate of 23% and a two-year rate of 10%. In patients treated with over 40Gy, the survival time for radiotherapy alone was 5.1 months, with a 1-year survival rate of 9.5%; relief of specific neurologic symptoms was noted in 80%. The longest survival was noted in a patient with a single brain metastasis, who, to date, has survived for five years and two months following 60Gy of irradiation. Patients with the following clinical conditions should have a good prognosis: (1) no further metastases in other sites, or well controlled if existing, (2) no symptoms of NF (neurological function: RTOG) or slight, and improved NF by treatment, (3) surgical candidate, (4) good response to initial treatment on CT or MRI. Despite a bad prognosis in general, brain metastasis from breast cancer can be treated affirmatively, if these clinical conditions are fulfilled.