Inclusion Criteria:

- Males and females greater than or equal to 18 years of age.

- Histologically confirmed recurrent (inoperable) or metastatic adenocarcinoma of the
esophagus, gastroesophageal junction, or stomach.

- At least one bidimensionally measurable lesion, not previously irradiated, with a
diameter that meets RECIST criteria, that can be serially measured. Intraluminal
tumors, evaluable only by endoscopy, are not acceptable as target lesions.

- Karnofsky Performance Score greater than or equal to 70%.

- Subjects must be in the second line therapy setting, thus they must have experienced
progression following treatment with one (and only one) prior chemotherapy regimen
used for the treatment of unresectable locally advanced, recurrent, or metastatic
disease.

- Recovery from any serious (grade 3 or higher) toxic effects of prior radiation
therapy.

- Adequate hematologic profile: absolute neutrophil count greater than or equal to
1,500/mm3; hemoglobin greater than or equal to 9 g/dL; hematocrit greater than or
equal to 30% (transfusion allowed); and platelet count greater than or equal to
100,000/mm3.

- Adequate hepatic function: bilirubin less than or equal to 1.5 mg/dL; AST and ALT
less that 2.5 X ULN (5 X ULN if liver involved with tumor); alkaline phosphatase less
than 5 X ULN

- Adequate renal function; serum creatinine less than or equal to 1.5 mg/dL or
calculated creatinine clearance greater than 50 mL/min.

- Both male and female subjects of childbearing potential must be using a contraceptive
method that is medically acceptable to the investigative center.

- Disease-free from a prior malignancy, other than non-melanoma skin cancer or
carcinoma in-situ of the cervix, for greater than 5 years.

Exclusion Criteria:

- Unstable angina or class III or IV New York Heart Association heart disease.

- CNS metastases.

- Pregnant or breast-feeding.

- Uncontrolled seizure disorder.

- Ongoing (grade 3 or higher) stomatitis, esophagopharyngitis, or uncontrolled
diarrhea.

- Impaired nutritional status as evidenced by a serum albumin of 2.7 mg/dL or less.

- Major surgery, chemotherapy, immunotherapy, or radiotherapy during the 28 days
preceding the first study treatment. Concomitant anticancer therapy (chemotherapy,
immunotherapy, or radiation) or other investigational agents during study
participation or 28 days prior to study participation.