This year, approximately 40% of the 28,300 patients diagnosed with pancreatic carcinoma in the United States will present with locally advanced disease. Radiotherapeutic approaches are often employed, as these patients have unresectable tumors by virtue of local invasion into the retroperitoneal vessels in the absence of clinically detectable metastases. These treatments include external-beam irradiation with and without fluorouracil (5-FU)-based chemotherapy, intraoperative irradiation, and more recently, external-beam irradiation with new systemic agents, such as gemcitabine (Gemzar).