RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Giving the drugs in different combinations may kill more tumor cells. Chemoprotective drugs such as triacetyluridine may protect normal cells from the side effects of chemotherapy. It is not yet known which chemotherapy regimen is more effective in treating pancreatic cancer.

PURPOSE: Randomized phase III trial to compare the effectiveness of fluorouracil plus triacetyluridine with that of gemcitabine in treating patients who have locally advanced or metastatic pancreatic cancer that cannot be treated with surgery.

OBJECTIVES:

• Compare the survival of patients with unresectable locally advanced or metastatic pancreatic cancer treated with triacetyluridine and high-dose fluorouracil vs gemcitabine.
• Compare the time to tumor progression, overall response rate, and response duration in patients treated with these regimens.
• Compare the safety of these regimens in these patients.

OUTLINE: This is a randomized, open-label, multicenter study. Patients are stratified according to disease stage (II or III vs IV). Patients are randomized to 1 of 2 treatment arms.

• Arm I: Patients receive high-dose fluorouracil (5-FU) IV over 30 minutes once weekly on weeks 1-3 followed by 1 week of rest. After each dose of 5-FU, patients receive oral triacetyluridine every 8 hours for a total of 8 doses. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.
• Arm II: Patients receive gemcitabine IV over 30 minutes once weekly on weeks 1-7 followed by 1 week of rest (course 1). Subsequent courses are given on weeks 1-3. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.

Patients are followed for survival.

PROJECTED ACCRUAL: A total of 260 patients (130 per treatment arm) will be accrued for this study within 30 months.

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed adenocarcinoma of the pancreas

  • Unresectable locally advanced or metastatic disease

    • Stage II, III, or IV
• Measurable or evaluable disease
• No elevated tumor marker (CA 19-9) only
• No clinically significant third-space fluid accumulation (e.g., ascites or pleural effusion)
• No carcinoid, islet cell, or lymphoma of the pancreas
• No prior or concurrent brain or leptomeningeal metastases

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• Karnofsky 70-100%

Life expectancy:

• At least 3 months

Hematopoietic:

• WBC at least 3,500/mm^3
• Platelet count at least 100,000/mm^3
• Hemoglobin at least 9.5 g/dL

Hepatic:

• Bilirubin no greater than 2.0 mg/dL
• ALT or AST less than 3 times upper limit of normal (ULN) (5 times ULN if liver metastases present)
• No uncontrolled hepatic dysfunction

Renal:

• Creatinine less than 2.0 mg/dL
• No uncontrolled renal dysfunction

Cardiovascular:

• No uncontrolled cardiovascular disease requiring therapy, including the following:

  • Angina
  • Arrhythmias
  • Uncompensated cardiac failure
  • Myocardial infarction within the past 6 months

Pulmonary:

• No uncontrolled pulmonary dysfunction

Gastrointestinal:

• Able to take and/or retain oral medication
• No uncontrolled malabsorption syndrome or any other condition that would interfere with intestinal absorption

Other:

• No known allergy to fluorouracil (5-FU), gemcitabine, triacetyluridine, or any of their components
• No dihydropyrimidine-dehydrogenase deficiency
• No active uncontrolled infection
• No uncontrolled neurologic or psychiatric dysfunction
• No other malignancy except previously resected basal cell cancer or curatively resected stage I or less cervical cancer that has been disease free for at least 5 years
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• HIV negative

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No concurrent biologic therapy (including immunotherapy) for cancer

Chemotherapy:

• No prior chemotherapy for cancer other than as a radiosensitizer
• No prior 5-FU or gemcitabine other than as a radiosensitizer
• No prior triacetyluridine
• No other concurrent chemotherapy (including leucovorin calcium) for cancer

Endocrine therapy:

• No concurrent hormonal therapy for cancer
• Concurrent megestrol, oral contraceptives, or postmenopausal estrogen replacement therapy allowed

Radiotherapy:

• Prior radiotherapy allowed
• No concurrent radiotherapy

Surgery:

• See Disease Characteristics
• Prior resection of pancreas allowed

Other:

• At least 30 days since prior investigational drug or therapeutic device
• No other concurrent anticancer therapy
• No other concurrent investigational drugs or devices
• No concurrent drugs that would interact adversely with 5-FU or gemcitabine