AIMS AND BACKGROUND: The purpose of the present retrospective study was to evaluate efficacy and safety of a lower dose-intensity capecitabine monotherapy regimen in heavily pretreated patients with metastatic breast cancer. METHODS: Patients with metastatic breast cancer who had been administered capecitabine monotherapy between June 2003 and August 2004 at our hospital were retrospectively reviewed. Oral capecitabine (828 mg/m2) was given twice daily for three weeks followed by a one-week rest period; this was repeated every four weeks. RESULTS: One-hundred and two patients were assessed. Median follow-up of patients was 16.4 months. One hundred patients (98%) had been pretreated with either anthracyclines or taxanes, 81 patients (79%) with both anthracyclines and taxanes. Response rate was 17% (95% CI, 9-24%), and clinical benefit rate was 41% (95% CI, 32-51%). Median time-to-treatment failure was 4.9 months, and median overall survival time was 24.3 months. This regimen was well tolerated. The most frequent grade 3 or 4 adverse event was hand-foot syndrome (6%). Other grade 3 or 4 adverse events were seen in only 1%-3% of patients. CONCLUSIONS: Intermittent capecitabine monotherapy with lower dose intensity achieved a high tumor control rate with low toxicity in heavily pretreated metastatic breast cancer patients.