Capecitabine and Oxaliplatin With or Without Cetuximab in Treating Patients With Metastatic Colorectal Cancer That Cannot Be Removed By Surgery

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed metastatic colorectal cancer Unresectable disease Primary tumor or metastases must be epidermal growth factor receptor-positive by immunohistochemistry Measurable disease, defined as ≥ 1 unidimensionally measurable lesion ≥ 20 mm by conventional techniques OR ≥ 10 mm by CT scan Measurable lesion must not be in a previously irradiated area No prior or current CNS metastases PATIENT CHARACTERISTICS: Age 18 and over Performance status WHO 0-1 Life expectancy Not specified Hematopoietic Absolute neutrophil count ≥ 1,500/mm^3 Platelet count ≥ 100,000/mm^3 Hepatic Bilirubin normal Renal Creatinine clearance > 50 ml/min Cardiovascular No New York Heart Association class III or IV congestive heart failure No symptomatic coronary artery disease No uncontrolled cardiac arrhythmia No myocardial infarction within the past 12 months No other significant cardiac disease Other Not pregnant or nursing Fertile patients must use effective contraception during and for 12 months after study participation Negative pregnancy test No peripheral neuropathy of any origin > grade 1 (e.g., alcohol or diabetes) No nausea, vomiting, or malabsorption syndrome that would preclude ingestion or absorption of oral medication No severe reaction attributed to fluoropyrimidine therapy No known hypersensitivity to fluorouracil or any other component of the trial drugs No known dihydropyrimidine dehydrogenase deficiency No other medical condition (e.g., uncontrolled diabetes or active autoimmune disease), geographical situation, or psychiatric disorder that would preclude study compliance No other malignancy within the past 5 years except adequately treated carcinoma in situ of the cervix or localized nonmelanoma skin cancer PRIOR CONCURRENT THERAPY: Biologic therapy Not specified Chemotherapy No prior chemotherapy for advanced or metastatic cancer At least 6 months since prior adjuvant chemotherapy Endocrine therapy Not specified Radiotherapy Not specified Surgery Not specified Other At least 30 days since prior experimental drugs No other concurrent experimental drugs No concurrent drugs that are contraindicated for use with the trial drugs No other concurrent anticancer therapy No concurrent sorivudine or any of its chemically-related analogues (e.g., lamivudine)