DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed primary inoperable or metastatic pancreatic adenocarcinoma
• No CNS metastases

PATIENT CHARACTERISTICS:

Age:

• Over 18

Performance status:

• Karnofsky 60-100%

Life expectancy:

• Not specified

Hematopoietic:

• WBC at least 3,500/mm^3
• Platelet count at least 100,000/mm^3
• Hemoglobin at least 10.0 g/dL

Hepatic:

• Bilirubin no greater than 5 times normal
• AST/ALT no greater than 5 times normal
• Alkaline phosphatase no greater than 5 times normal

Renal:

• Creatinine clearance at least 30 mL/min

Gastrointestinal:

• No grade 2 or greater nausea or grade 1 or greater vomiting
• No medical condition that would interfere with taking oral medications or with gastrointestinal absorption (e.g., small bowel obstruction)

Other:

• No prior unanticipated severe reaction to fluoropyrimidine therapy
• No known hypersensitivity to fluorouracil
• No known dihydropyrimidine dehydrogenase deficiency
• No active infection
• No other serious concurrent systemic disorders that would preclude study participation
• No other malignancy within the past 5 years except adequately treated carcinoma in situ of the cervix or basal cell skin cancer
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• No prior capecitabine
• No prior chemotherapy for advanced pancreatic cancer
• At least 1 year since prior radiochemotherapy for pancreatic cancer

Endocrine therapy:

• Not specified

Radiotherapy:

• See Chemotherapy
• At least 1 year since prior adjuvant radiotherapy for pancreatic cancer
• No concurrent radiotherapy

Surgery:

• Prior Whipple procedure or duodenal bypass allowed

Other:

• At least 1 month since prior investigational agents
• No concurrent sorivudine or its chemically related analogues (e.g., brivudine)
• No other concurrent anticancer or investigational drugs