Cetuximab and Capecitabine in Treating Patients With Metastatic Colorectal Cancer That Failed Irinotecan Treatment

DISEASE CHARACTERISTICS: * Diagnosis of metastatic colorectal cancer * Measurable disease * Disease progression during prior fluoropyrimidine-containing therapy comprising irinotecan with or without oxaliplatin * Received standard first- and second-line irinotecan and oxaliplatin-based therapy * Patients who completed 1 prior treatment for metastatic disease but refused standard second-line therapy are eligible * Patients who's disease progressed within 6 months of previous therapy are eligible * EGFR negative patients allowed * No untreated or uncontrolled brain metastasis PATIENT CHARACTERISTICS: * ECOG performance status 0-2 * Absolute neutrophil count ≥ 1,500/μL * Platelet count ≥ 100,000/μL * ALT ≤ 5 times upper limit of normal (ULN) * Alkaline phosphatase ≤ 5 times ULN * Serum creatinine ≤ 1.5 mg/dL * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception * No other prior malignancy within the past 5 years except nonmelanoma skin cancer or carcinoma in situ of the cervix * No serious intercurrent infections or medical problems * No active or uncontrolled infections * No significant history of uncontrolled cardiac disease, including any of the following: * Uncontrolled hypertension * Unstable angina * Myocardial infarction within the past 6 months * Uncontrolled congestive heart failure * Cardiomyopathy with decreased ejection fraction * No prior severe infusion reaction to a monoclonal antibody * No known dihydropyrimidine dehydrogenase deficiency or evidence of past hypersensitivity to fluoropyrimidine PRIOR CONCURRENT THERAPY: * See Disease Characteristics * No more than 2 prior treatments for metastatic colorectal cancer * More than 2 weeks since prior therapy * Prior radiotherapy allowed if \< 30% of bone marrow involvement * No other concurrent investigational agents * No concurrent highly active antiretroviral therapy for HIV-positive patients * No prior therapy that specifically and directly targets the EGFR pathway