DISEASE CHARACTERISTICS:

• Histologically confirmed colorectal cancer

  • Metastatic disease
• Epidermal growth factor receptor (EGFR)-positive by immunochemistry
• Measurable or evaluable disease

• Not amenable to standard curative therapy

  • Best supportive care is the only available option

• Must have received a prior thymidylate synthase inhibitor (e.g., fluorouracil, capecitabine, raltitrexed, or fluorouracil-uracil) in the adjuvant or metastatic setting

  • Combination therapy with oxaliplatin or irinotecan allowed
• Must have failed* a prior regimen containing irinotecan and a prior regimen containing oxaliplatin for metastatic disease OR relapsed within 6 months after an adjuvant regimen containing irinotecan or oxaliplatin OR have documented unsuitability for such regimens
• No symptomatic CNS metastases NOTE: *Failure is defined as either disease progression (clinical or radiological) or intolerance to the regimen

PATIENT CHARACTERISTICS:

Age

• 16 and over

Performance status

• ECOG 0-2

Life expectancy

• Not specified

Hematopoietic

• See Disease Characteristics
• Absolute granulocyte count ≥ 1,500/mm^3
• Platelet count ≥ 75,000/mm^3
• Hemoglobin ≥ 8.0 g/dL

Hepatic

• AST and ALT ≤ 5 times upper limit of normal (ULN)
• Bilirubin ≤ 2.5 times ULN

Renal

• Creatinine ≤ 1.5 times ULN

Cardiovascular

• No uncontrolled angina
• No arrhythmias
• No cardiomyopathy
• No congestive heart failure
• No myocardial infarction* within the past 6 months NOTE: *Pre-treatment ECG as only evidence of infarction is allowed

Pulmonary

• No severe restrictive lung disease
• No interstitial lung disease by chest x-ray

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception for 4 weeks before, during, and for 4 weeks after study treatment
• No active pathological condition that would preclude study participation
• No psychological or geographical condition that would preclude study compliance
• No other malignancy within the past 5 years except adequately treated non-melanoma skin cancer or carcinoma in situ of the cervix

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior cetuximab
• No prior murine monoclonal antibody therapy (e.g., edrecolomab)

Chemotherapy

• See Disease Characteristics
• At least 4 weeks since prior chemotherapy and recovered
• No concurrent chemotherapy

Radiotherapy

• See Disease Characteristics
• At least 4 weeks since prior radiotherapy and recovered
• Concurrent palliative radiotherapy allowed except to index lesions

Surgery

• At least 4 weeks since prior major surgery and recovered

Other

• No prior EGFR-targeted therapy (e.g., erlotinib or gefitinib)
• More than 30 days since prior experimental therapeutic agents
• More than 4 weeks since prior investigational agents
• No concurrent enrollment in another clinical study
• No other concurrent EGFR-targeted therapy
• No other concurrent non-cytotoxic experimental agents