A randomized controlled trial is being conducted in Japan to compare hepatectomy alone with hepatectomy followed by adjuvant chemotherapy as treatment in patients with curatively resected liver metastases from colorectal cancer to improve survival with intensive chemotherapy. Between 42 and 70 days after liver resection, patients are randomly assigned to either hepatectomy alone or hepatectomy followed by 12 cycles of modified FOLFOX6 (mFOLFOX6) regimen. A total of 300 patients (including 78 patients in Phase II) will be accrued from 38 institutions within 3 years. The primary endpoint is treatment compliance at nine courses of mFOLFOX6 regimen in Phase II and disease-free survival in Phase III. The secondary endpoints are overall survival, incidence of adverse events and patterns of recurrence.