Fluorouracil, Gemcitabine, and Radiation Therapy in Treating Patients With Cancer of the Pancreas

RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Radiation therapy uses high-energy x-rays to damage tumor cells. Combining radiation therapy with chemotherapy may kill more tumor cells. It is not yet known which treatment regimen is most effective for pancreatic cancer.

PURPOSE: Randomized phase III trial to compare the effectiveness of fluorouracil and gemcitabine plus radiation therapy in treating patients with cancer of the pancreas who have undergone surgery.

OBJECTIVES:

* Compare the overall and disease-free survival of patients with resected adenocarcinoma of the pancreas treated with adjuvant fluorouracil-based chemoradiotherapy preceded and followed by fluorouracil vs gemcitabine.
* Compare the local-regional and distant disease control in patients treated with these regimens.
* Compare the acute and late toxic effects of these regimens in these patients.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to nodal involvement (yes vs no), tumor diameter (less than 3 cm vs 3 cm or greater), and surgical margins (negative vs positive vs unknown). Patients are randomized to one of two treatment arms.

* Arm I: Beginning 3-8 weeks after definitive surgical resection, patients receive fluorouracil IV continuously for 3 weeks. Beginning 1-2 weeks later, patients receive fluorouracil IV continuously concurrently with radiotherapy 5 days a week for 5.5 weeks. Beginning 3-5 weeks after completion of chemoradiotherapy, patients receive fluorouracil IV continuously for 4 weeks every 6 weeks for 2 courses.
* Arm II: Beginning 3-8 weeks after definitive surgical resection, patients receive gemcitabine IV once weekly for 3 weeks. Beginning 1-2 weeks later, patients receive chemoradiotherapy as in arm I. Beginning 3-5 weeks after completion of chemoradiotherapy, patients receive gemcitabine IV once weekly for 3 weeks every 4 weeks for 3 courses.

Patients are followed every 3 months for 1 year, every 6 months for 2 years, and then annually thereafter.

PROJECTED ACCRUAL: A total of 518 patients will be accrued for this study within 8.6 years.

Eligibility Criteria:
DISEASE CHARACTERISTICS:

* Histologically confirmed adenocarcinoma of the pancreas

  * Stage T1-4, N0-1 (stage I-IVA)
  * No M1 or NX staging
  * Primary tumor of the pancreas (pancreatic head, neck, uncinate process, or body/tail) and maximum diameter/dimension and tumor status at surgical margin known
* Prior potentially curative gross resection within 3-8 weeks before study
* No non-adenocarcinomas, adenosquamous carcinomas, islet cell carcinomas, cystadenomas, cystadenocarcinomas, carcinoid tumors, duodenal carcinomas, distal bile duct carcinoma, or ampullary carcinoma
* No recurrent disease
* Post-resection CA-19-9 level required

PATIENT CHARACTERISTICS:

Age:

* 18 and over

Performance status:

* Karnofsky 60-100%

Life expectancy:

* Not specified

Hematopoietic:

* WBC at least 3,000/mm\^3
* Platelet count at least 100,000/mm\^3

Hepatic:

* Bilirubin no greater than 1.5 times upper limit of normal (ULN)
* SGOT no greater than 5 times ULN

Renal:

* Creatinine no greater than 1.5 times ULN

Other:

* No significant nausea or vomiting
* No prior malignancy within the past 5 years except nonmelanomatous skin cancer or carcinoma in situ of the cervix
* Able to maintain adequate nutrition (at least 1,500 calories/day)

  * Feeding tube allowed
* Not pregnant
* Negative pregnancy test
* Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* Not specified

Chemotherapy:

* No prior chemotherapy

Endocrine therapy:

* Not specified

Radiotherapy:

* No prior radiotherapy

Surgery:

* See Disease Characteristics