Palliative Stereotactic Radiation for Pancreatic or Periampullary Adenocarcinoma

Inclusion Criteria: * 18 years of age or older * Karnofsky Performance Status greater than or equal to 70% * confirmed pancreatic or periampullary adenocarcinoma * pancreatic or periampullary tumor less than 8.0 cm in greatest axial dimension * Either: * standard of care treatment for pancreatic cancer that included radiation therapy \* patients may be receiving continued chemotherapy post initial CRT. or * standard of care treatment for pancreatic cancer that did not include radiation therapy \* patients must have attempted chemotherapy upon initial diagnosis * acceptable organ and marrow function as determined by blood tests * ability to understand and give consent * must be a patient to be treated with SBRT only at Johns Hopkins Hospital * life expectancy of greater than 3 months Exclusion Criteria: * extensive metastatic disease * performance status of less than 70 * children are excluded form the study * no uncontrolled intercurrent illness * no concurrent malignancy other than melanoma * pregnant or breast feeding women are excluded * women who are not post-menopausal and have a positive pregnancy test * life expectancy of less than 3 months