No standard treatment option has yet been established for patients with recurrent or residual disease after definitive treatment of pancreatic or periampullary cancers (duodenal, ampullary, bile duct). Linac based stereotactic body radiation therapy (SBRT) administered in 1-3 fractions has been shown to be an effective treatment option for patients with unresectable, locally advanced pancreatic adenocarcinoma, achieving local control rates of 84-92% at one year. Associated late gastrointestinal toxicity rates have been reported to be 22-25% at 1 year. We hypothesize that similarly excellent local control rates (80-90% at one year) with a reasonable rate of toxicity (≤20%) can be achieved using Linac based SBRT delivered as 5 Gy x 5 for patients with local failure (remaining disease) after previous treatment with conventional chemoradiation therapy (CRT) with or without surgery and as 6.6 Gy x 5 for radiation-naïve patients with local failure (remaining disease) after previous treatment with surgery and/or chemotherapy. The toxicities of note for this trial are grade 2 and greater gastritis, fistula, enteritis, ulcer, or any other grade 3 or greater gastrointestinal toxicity.
