Randomized phase 2 study of mFOLFOX6 plus bevacizumab versus modified OPTIMOX plus bevacizumab for metastatic colorectal cancer

INTERVENTION: After 8 cycles of mFOLFOX 6 plus bevacizumab, patients receive UFT/LV with bevacizumab (until 5 cycles are completed or disease progression). And then, patients receive modified FOLFOX6 plus bevacizumab until disease progression. Patients receive mFOLFOX6 plus bevacizumab until disease progression. CONDITION: colorectal cancer PRIMARY OUTCOME: disease control survival SECONDARY OUTCOME: Progression‐free survival; Overall survival; The incidence of adverse events INCLUSION CRITERIA: 1) unresectable or recurrent colorectal cancer histologically diagnosted adenocarcinoma of the colon or rectum. 2) Age more than 20years and less than 75 years. 3) No prior therapies for metastatic and/or recurrent disease. Prior adjuvant therapy is allowed if it is completed at least 6 months before registration. 4) ECOG performance status of 0 or 1 . 5) Required baseline laboratory parameters (within 7 days before registration): WBC more than 4000 and WBC less than 12000/mm3 Neutrophils more than 2000/mm3 Plt more than 100,000/mm3 Hb more than 9.0g/dl GOT less than 100 IU/l GPT less than 100 IU/l T‐Bil less than 1.5mg/dl Creatinine less than 1.5mg/dl 6) Signed informed consent of the patient for the registration.