Respiratory-gated Stereotactic Body Radiation Therapy for Adenocarcinoma of the Pancreas or Periampullary Region

Patients will receive 5 fractions of 5 gray (Gy) or 6.6 Gy delivered over a five-day period based on whether or not they have received prior radiation therapy to the pancreatic region. Treatment may be delivered over 2 weeks, provided that the patient receives at least 2 fractions per week. Initial patient positioning will be based on volumetric kV (cone-beam computerized tomography) imaging with shifts to bony anatomy as appropriate. Orthogonal kV/MV or kV/kV projection imaging will be used to verify the location of the fiducials prior to delivery of the first treatment beam. A secondary shift based on the location of fiducials may be utilized, as indicated by the position of the fiducials. For free-breathing treatments, kV fluoroscopic images should be obtained to confirm the anticipated position of these fiducials during the entire respiratory cycle. Active monitoring of treatment delivery accuracy will be accomplished using kV and/or MV projection imaging, either immediately before or during all (or a subset of) treatment fields. Patient-specific dosimetric quality assurance (QA) will be performed as per standard practice in the Department of Radiation Oncology, Indiana University School of Medicine.