RATIONALE: Radiation therapy uses high-energy x-rays to damage tumor cells. Gemcitabine may make tumor cells more sensitive to radiation therapy. Combining chemotherapy with radiation therapy after surgery may kill more tumor cells.

PURPOSE: Phase II trial to study the effectiveness of combining gemcitabine with radiation therapy in treating patients who have undergone surgery to remove cancer of the pancreas.

OBJECTIVES:

• Determine the time to disease progression, local control, and survival of patients with previously resected pancreatic cancer treated with adjuvant gemcitabine and radiotherapy.

OUTLINE: This is a multicenter study.

Patients receive gemcitabine IV over 30-60 minutes on days 1, 4, 8, 11, 15, 18, 22, 25, 29, and 32 and undergo radiotherapy on days 1-5, 8-12, 15-19, 22-26, 29-33, and 36-38 in the absence of disease progression or unacceptable toxicity.

Beginning at least 4 weeks after chemoradiotherapy, patients without disease progression and with less than 10% weight loss during study receive additional gemcitabine IV over 30 minutes on days 1, 8, and 15. Treatment repeats every 28 days for a total of 2 courses.

Patients are followed every 8 weeks for 6 months and then every 3 months for up to 2 years.

PROJECTED ACCRUAL: A total of 72 patients will be accrued for this study within 2.2 or 3.4 years.

DISEASE CHARACTERISTICS:

• Histologically confirmed invasive adenocarcinoma of the pancreas

  • Prior gross total resection via a pancreaticoduodenectomy (Whipple resection or total pancreatectomy) within the past 2 months

• No clinical evidence of gross residual disease at time of surgery

  • No focally positive margins (tumor at the margin)

• No unresected nodal disease or metastatic disease to the liver, peritoneal surfaces, or elsewhere

PATIENT CHARACTERISTICS:

Age:

• Over 18

Performance status:

• ECOG 0-2

Life expectancy:

• More than 6 months

Hematopoietic:

• Granulocyte count greater than 1,500/mm3
• Hemoglobin greater than 10 g/dL
• Platelet count greater than 100,000/mm3

Hepatic:

• Bilirubin less than 2.0 mg/dL

Renal:

• Creatinine less than 2.0 mg/dL

Other:

• Able to maintain adequate oral nutrition
• Documented stable weight (no more than 5 lbs weight loss) for at least 2 weeks prior to study
• No other malignancy within the past 2 years except inactive nonmelanoma skin cancer or carcinoma in situ of the cervix or breast
• Non-metastatic prostate cancer allowed if more than 2 year survival likely
• No other serious medical or psychiatric illness that would preclude study or limit survival to less than 2 years
• Not pregnant
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No concurrent routine growth factors

Chemotherapy:

• No prior chemotherapy for pancreatic cancer

Endocrine therapy:

• Not specified

Radiotherapy:

• No prior abdominal radiotherapy for pancreatic cancer

Surgery:

• See Disease Characteristics