Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically or cytologically confirmed diagnosis of 1 of the following:

- Adenocarcinoma or squamous cell carcinoma of the esophagus

- Adenocarcinoma of the gastroesophageal junction

- Adenocarcinoma of the stomach

- Metastatic disease

- Measurable disease by diagnostic CT scan or MRI

- Failed prior treatment with cisplatin and irinotecan hydrochloride, defined by the
following:

- Radiographic progression within 12 weeks* from the last dose of prior cisplatin
and irinotecan hydrochloride, administered either as adjuvant or neoadjuvant
therapy, OR as therapy for metastatic disease NOTE: *Prior irinotecan
hydrochloride and cisplatin must have been administered within the past 12
weeks; other chemotherapy regimens may have been administered between the time
of disease progression or prior irinotecan hydrochloride/cisplatin and study
entry

- Pathologic tissue available for immunohistochemistry (IHC) staining for the epidermal
growth factor receptor (EGFR)

- Positive or negative EGFR by IHC allowed

PATIENT CHARACTERISTICS:

- ECOG performance status (PS) 0-1 OR Karnofsky PS 70-100%

- Life expectancy > 3 months

- WBC ≥ 3,000/mm³

- Absolute neutrophil count ≥ 1,500/mm³

- Platelet count ≥ 100,000/mm³

- Hemoglobin ≥ 9 g/dL

- Bilirubin normal

- AST and ALT < 2.5 times upper limit of normal (ULN) (5 times ULN if liver metastases
are present)

- Creatinine ≤ 2.0 mg/dL

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No prior severe infusion reaction to a monoclonal antibody

- No history of allergic reactions to compounds of similar chemical or biologic
composition to irinotecan hydrochloride, cisplatin, or other study agents

- No prior intolerance to irinotecan hydrochloride or cisplatin despite prior dose
attenuations

- No uncontrolled illness including, but not limited to, any of the following:

- Ongoing or active infection requiring parenteral antibiotics

- Symptomatic congestive heart failure

- Unstable angina pectoris

- Uncontrolled hypertension

- Clinically significant cardiac arrhythmia

- Myocardial infarction within the past 6 months

- HIV infection

- Psychiatric illness or social situations that would preclude study compliance

- No history of Gilbert's disease

- No medical condition or reason that would preclude study treatment

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- More than 3 weeks since prior chemotherapy or radiotherapy and recovered

- No more than 2 prior treatment regimens for metastatic disease

- No prior therapy specifically and directly targeting the epidermal growth factor
receptor pathway

- No prior anticancer murine or chimeric monoclonal antibody therapy

- Prior humanized monoclonal antibody therapy allowed

- No concurrent antiseizure medications known to affect the metabolism of irinotecan
hydrochloride, including phenytoin or phenobarbital

- No other concurrent investigational agents

- No other concurrent anticancer agents or therapies