DISEASE CHARACTERISTICS:

• Histologically confirmed unresectable adenocarcinoma of the pancreas
• No cystadenocarcinoma of the pancreas or pancreatic tumors of neuroendocrine origin

• Prior subtotal resection or gross residual disease

  • No microscopic residual disease only
• No metastatic disease outside of planned study radiotherapy field

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• ECOG 0-1

Life expectancy:

• Not specified

Hematopoietic:

• Absolute neutrophil count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3

Hepatic:

• Bilirubin no greater than 2 times upper limit of normal (ULN)
• AST no greater than 3 times ULN

Renal:

• Creatinine no greater than 1.5 times ULN

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• Able to maintain adequate oral nutrition
• No significant infection
• No other medical condition that would preclude study
• No other malignancy within the past 5 years except non-melanoma skin cancer
• No significant nausea or vomiting

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior or concurrent biologic therapy

Chemotherapy:

• No prior chemotherapy
• No other concurrent chemotherapy

Endocrine therapy:

• Not specified

Radiotherapy:

• See Disease Characteristics
• No prior radiotherapy that would overlap planned study radiotherapy fields

Surgery:

• See Disease Characteristics
• At least 21 days since prior laparotomy