DISEASE CHARACTERISTICS: Histologically confirmed nonmetastatic, unresectable pancreatic adenocarcinoma No evidence of metastatic disease in the major viscera and no peritoneal seeding Residual disease after resection (R-1 or -2 micro- and macroscopic residual) eligible if measurable disease on the post operative CT or MRI scan Recurrent disease following radical surgery is eligible All malignant disease must be encompassable within a single irradiation field Must be a radiographically assessable disease CT with 5 mm cuts or spiral CT