To evaluate tolerance to and efficacy of bevacizumab in the treatment of MCRC in elderly patients, we propose a phase II randomised study comparing a chemotherapy + bevacizumab arm with a chemotherapy alone arm in the first-line treatment of MCRC in patients aged 75 years and older.

This study is destined to continue as a phase III trial if both arms meet the selection criteria to show or not the benefits of treatment with bevacizumab combined with chemotherapy.

Inclusion Criteria:

• Patients aged 75 years or older
• ECOG ≤2
• histologically proven unresectable metastatic colorectal adenocarcinoma
• Measurable lesion according to RECIST criteria
• Absence of prior chemotherapy for metastatic disease. Adjuvant chemotherapy following resection of the primary tumor is authorized if completed more than 6 months previously
• Patients treated with anticoagulants (coumadin, warfarin) can be included if close surveillance of the INR can be ensured. A change to low-molecular-weight heparin is preferable as long as the indications are respected
• Completed geriatric self-questionnaire
• Completed "Team" geriatric questionnaire (including Spitzer QoL Index)
• Written informed consent

Exclusion Criteria:

• Estimated life expectancy < 3 months
• Non-resolved intestinal occlusion or sub-occlusion
• Cerebral metastasis
• Other evolutive malignant tumor (non-stabilized cancer for less than 2 years)
• Evolutive gastroduodenal ulcer, wound or bone fracture
• Active heart disease: uncontrolled hypertension, myocardial infarction In the previous 6 months, angina, non-compensated congestive heart failure
• Major surgery, except for biopsy, or irradiation in the 4 weeks preceding the start of treatment
• Polynuclear neutrophils <1500/mm3, platelets <100 000/mm3 or 24-h proteinuria > 1g
• History of arterial thromboembolic event (cerebrovascular accident, transient ischemic attack, subarachnoid hemorrhage) in the 12 months preceding the first dose of bevacizumab
• History of distal or visceral ischemia ≥ grade 2 in the 12 months preceding the first dose of bevacizumab
• History of life-threatening pulmonary embolism in the 6 months preceding the first dose of bevacizumab
• Impossibility to ensure regular follow-up