Inclusion Criteria:

- Primary colorectal cancer with unresectable metastatic lesion(s)

- At least one measurable lesion, confirmed by CT scan

- Male and female patients, aged ≥ 18 years

- ECOG performance score of 0 or 1 (within 1 week of study treatment start)

- Written informed consent

- Adequate general condition, cardiopulmonary functions and performance status

- Liver metastases no initially foreseen R0 resection of all hepatic lesions, but
deemed potentially resectable after response to downsizing therapy

Exclusion Criteria:

- Extrahepatic metastatic disease

- Prior systemic or local treatment for metastatic disease, prior therapy with a
biologic agent, prior adjuvant or neo-adjuvant chemotherapy, prior radiotherapy to
the liver, other concurrent chemotherapy

- Inadequate bone marrow, liver, renal function, uncontrolled hypertension

- Pregnancy or lactation