Inclusion Criteria

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