Electron Beam Intraoperative Radiation Therapy Following Chemoradiation in Patients With Pancreatic Cancer With Vascular Involvement

Inclusion Criteria: * Age ≥ 18 years * ECOG Performance Status 0-1 * Previous completion of at least three (3) months of EITHER gemcitabine plus nab-paclitaxel OR FOLFIRINOX (5-fluorouracil, oxaliplatin, irinotecan and leucovorin) * Previous completion of either stereotactic-body radiation therapy (SBRT) (minimum 24 Gy) or external beam irradiation (EBRT) (minimum 45 Gy) * Participation in any investigational drug study within 4 weeks preceding the start of study treatment is PERMITTED. * Women of childbearing potential (WOCBP) must use appropriate method(s) of contraception. WOCBP should use an adequate method to avoid pregnancy for 5 months after IORT. * Men who are sexually active with WOCBP must use any contraceptive method with a failure rate of less than 1% per year. Men receiving nivolumab and who are sexually active with WOCBP will be instructed to adhere to contraception for a period of 7 months after IORT. Women who are not of childbearing potential, i.e., who are postmenopausal or surgically sterile as well as azoospermic men do not require contraception. * Ability to understand and the willingness to sign a written informed consent document Exclusion Criteria: * Evidence of disease progression or distant metastases. * Pregnant or lactating women * Treatment for other invasive carcinomas within the last five years who are at greater than 5% risk of recurrence at time of eligibility screening. Carcinoma in-situ and basal cell carcinoma/ squamous cell carcinoma of…