DISEASE CHARACTERISTICS:

• Histologically confirmed unresectable locally advanced or metastatic adenocarcinoma of the stomach or gastroesophageal junction

• Measurable disease

  • At least 20 mm with conventional techniques OR
  • At least 10 mm with spiral CT scan

  • The following are not considered measurable:

    • Bone lesions
    • Leptomeningeal disease
    • Ascites
    • Pleural/pericardial effusion
    • Inflammatory breast disease
    • Lymphangitis cutis/pulmonis
    • Abdominal masses that are not confirmed or followed by imaging techniques
    • Cystic lesions
• No bone metastases as sole disease site
• No brain metastases

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• Zubrod 0-1
• Karnofsky 60-100%

Life expectancy:

• At least 12 weeks

Hematopoietic:

• Granulocyte count at least 1,500/mm^3
• Hemoglobin at least 8 g/dL
• Platelet count at least 100,000/mm^3
• No bleeding diathesis

Hepatic:

• Bilirubin no greater than 1.5 mg/dL
• Transaminases no greater than 2.5 times upper limit of normal

Renal:

• Creatinine no greater than 1.5 mg/dL
• Calcium no greater than 12 mg/dL
• No symptomatic hypercalcemia

Cardiovascular:

• No New York Heart Association class III or IV heart disease
• No angina, myocardial infarction, or congestive heart failure in past 6 months

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No serious concurrent infections, nonmalignant medical illnesses, or psychiatric disorders that may preclude study
• No other prior malignancy in past 5 years except nonmelanoma skin cancer or carcinoma in situ of the cervix

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• At least 6 months since prior adjuvant immunotherapy
• No prior immunotherapy outside of the adjuvant setting
• No concurrent immunotherapy

Chemotherapy:

• At least 6 months since prior adjuvant chemotherapy
• No prior chemotherapy outside of the adjuvant setting
• No other concurrent chemotherapy

Endocrine therapy:

• Not specified

Radiotherapy:

• At least 4 weeks since prior radiotherapy
• No prior radiotherapy to major bone marrow containing areas (pelvis, lumbar spine) or to study lesion
• No concurrent radiotherapy

Surgery:

• At least 1 week since prior minor surgery (3 weeks for major surgery) and recovered

Other:

• No concurrent anticoagulants