Pulse-low-dose Rate (PLDR) Radiation in Pancreatic Cancer

Inclusion Criteria:

* Patients must have histologically or cytologically-confirmed pancreatic adenocarcinoma.
* Patients must have non-metastatic pancreatic cancer not appropriate for immediate surgical resection. This includes the following:

  * Any involvement (defined as loss of fat plane on contrast CT) of any of the following vessels\*:

    * Common hepatic artery
    * Superior mesenteric artery
    * Celiac axis
    * Superior mesenteric vein
    * Portal vein
    * Aorta

      * These criteria will be judged by the operating surgeon in conjunction with a radiologist prior to enrollment.
  * Poor performance status not immediately conducive to radical surgery
  * Other clinical reasoning by the treating physicians that supports pre-operative chemoradiation
* Patients must have evaluable disease as measured by RECIST 1.1 criteria.
* Planned surgical resection at the time of enrollment (may be initially staged as resectable, borderline resectable, or locally-advanced/unresectable).
* Eastern Cooperative Oncology Group, or ECOG, performance status 0-2.
* Adequate bone marrow, hepatic, renal function.

  * ANC ³ 1,500/ml and PLT ³ 100,000/ml
  * Bilirubin less than 1.5 ULN
  * AST and ALT \< 3X ULN
  * Serum Creatinine \<1.5X ULN
* Prior chemotherapy allowed, but not mandatory. Patients who have undergone chemotherapy prior to participating in this study must have had a 2 week washout period at the time of signing the consent form.
* Women of childbearing potential must be non-pregnant (negative pregnancy test within 72 hours prior to registration. Postmenopausal woman must have been amenorrheic and nonlactating for at least 12 months to be considered of non-childbearing potential. Men and women of child bearing potential must be willing to exercise an effective form of birth control (abstinence/contraception) while on study and for 3 months after therapy is completed. Please refer to section 6.4 for additional detail.
* Age \> 18 years
* Participants must sign a written informed consent and HIPAA consent prior to performance of study-specific procedures or assessments and must be willing to comply with treatment and follow up.

Exclusion Criteria:

* Radiological or cytologically confirmed metastatic disease
* Patients who have had any prior therapy for pancreatic cancer, except chemotherapy (see 6.1.7)
* Concurrent non-study chemotherapy or biologic therapy
* A history of ataxia telangiectasia or other documented history of radiation hypersensitivity
* Scleroderma or active connective tissue disease
* Active inflammatory bowel disease
* Serious, active infections requiring treatment with IV antibiotics
* Uncontrolled intercurrent illness including, but not limited to, psychiatric illness/social situations that would limit compliance with study requirements.