Safety and Immunological Effect of Pembrolizumab in Resectable or Borderline Resectable Pancreatic Cancer

Inclusion Criteria: 1. Measurable disease based on Response Evaluation Criteria in Solid Tumors (RECIST) 1. 2. Performance status of 0 or 1 on the Eastern Cooperative Oncology Group (ECOG) Performance Scale 3. Adequate organ function 4. In subjects requiring biliary decompression, metal stent or drainage using percutaneous transhepatic cholangiogram (PTC) are allowed Exclusion Criteria: 1. Immunodeficiency or taking steroid or any other form of immunosuppressive therapy 2. Has a plastic biliary stent for decompression 3. Metastatic disease 4. Prior treatment for pancreatic cancer (other than 4-8 cycles of Folfirinox) or prior treatment with radiation for other diagnoses to the expected pancreatic cancer treatment area 5. Active autoimmune disease 6. Pregnancy or Nursing 7. Known history of Human Immunodeficiency Virus (HIV) or Hepatitis B or C 8. Prior monoclonal antibody within 4 weeks prior to study Day 1 9. Known additional malignancy that is progressing or requires active treatment 10. Evidence of interstitial lung disease or active, non-infectious pneumonitis 11. Active infection requiring systemic therapy 12. Prior therapy with an anti-Program Death (PD-1) antibody, anti-PD-L1, anti-PD-L2, or anti-Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) antibody