Safety and Efficacy Study of XELOX vs. Oxaliplatin+5-FU CI as First Line Treatment in Metastatic Colorectal Cancer

Inclusion Criteria: Written informed consent. Men and women \> or = 18 years Karnofsky functional status \>or=70% at the time of enrollment in study Histologically confirmed diagnosis of CRC Patients must not have received chemotherapy (exception: adjuvant treatment \> 12 months following conclusion of treatment) Presence of at least one lesion detectable by two-dimensional measurement.. Life expectancy greater than 3 months. Exclusion Criteria: Pregnant or nursing woman Prior administration of systemic immunotherapy, chemotherapy (exception: 5-FU as adjuvant treatment \> 12 months following conclusion of treatment) Evidence of allergic reaction to any of the treatment components Clinically relevant myocardial disease or history of myocardial infarction in the past 12 months Documented or suspected cerebral and/or leptomeningeal metastases. Prior malignant tumour in past 5 years, except history of basal cell skin carcinoma or pre-invasive cervical carcinoma. Neutrophil count \< 1.5 x 109/l , platelets \< 100 X 109/l serum creatinine \> 1.5 x ULN. Total bilirubin count \> 2 x ULN Alkaline Phosphatase \> \> 2.5 x ULN (\> 5 x ULN if there are hepatic metastases) Aspartate aminotransferase (AST/SGOT) and alanine aminotransferase (ALT/SGPT) \> 2.5 x ULN (\> 5 x ULN if there are hepatic metastases, \> 10 x ULN if there are bone metastases) Creatinine clearance \< 30 ml/min Surgery within 4 weeks prior to enrollment in the study. Any investigational drug during the 4 weeks prior to enrolment. Uncontrolled active infection Any medical or psychological disorder which, in the opinion of the investigator, does not allow the patient to conclude the study or sign the informed consent \-