DISEASE CHARACTERISTICS: Histologically confirmed adenocarcinoma of the pancreas Locoregional and not amenable to surgery based on 1 or more of the following: Size of pancreatic tumor greater than 5 cm Lymph nodes bulky, greater than 2 cm, but within radiation port Vascular involvement or impingement of major vessels (e.g., superior mesenteric artery, superior mesenteric vein, portal vein, hepatic artery) Involvement of colon (head lesions) or involvement of adrenal, kidney, or colon (tail lesions) Patients must be registered and begin treatment within 42 days of surgical staging No metastatic disease or nodal disease outside of radiation port documented by CT scan or MRI and chest x-ray