DISEASE CHARACTERISTICS:

• Histologically confirmed pancreatic adenocarcinoma
• Complete macroscopic resection of tumor within past 30 days
• No residual visceral or peritoneal metastasis
• Involvement of Vater's ampulla or extrahepatic bile duct allowed
• No vesicular or intrahepatic cholangiocarcinomas

PATIENT CHARACTERISTICS:

Age:

• 18 to 75

Performance status:

• ECOG 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Absolute neutrophil count greater than 1,500/mm^3
• Platelet count greater than 100,000/mm^3

Hepatic:

• Alkaline phosphatase less than 3 times normal
• Bilirubin less than 1.5 times normal

Renal:

• Creatinine less than 1.5 times normal

Cardiovascular:

• No serious cardiac failure

Pulmonary:

• No serious respiratory failure

Other:

• No other untreatable malignant tumors
• No serious psychological, familial, social, or geographical conditions that would preclude study

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• No prior chemotherapy for pancreatic adenocarcinoma

Endocrine therapy:

• Not specified

Radiotherapy:

• No prior radiotherapy for pancreatic adenocarcinoma
• No prior radiotherapy in an anatomically proximal region to treatment area

Surgery:

• See Disease Characteristics