Chemoimmunotherapy and Radiation in Pancreatic Cancer

This study is for borderline resectable and advanced pancreatic cancer patients. Patients
will receive chemotherapy with gemcitabine and immunotherapy with daily tadalafil during the
first 21 days of treatment. On study day 22, patients will receive the first of three planned
doses of radiation therapy and continue daily tadalafil. Patients are then evaluated to
determine if they are candidates for pancreaticoduodenectomy. Patients who are not candidates
will continue daily tadalafil and receive gemcitabine chemotherapy. Patients who have surgery
will resume daily tadalafil and gemcitabine chemotherapy following recovery from surgery.
Patients will receive up to four cycles of gemcitabine.

Inclusion Criteria:

- Pancreatic adenocarcinoma

- Locally advanced unresectable disease, or borderline resectable disease

- ECOG (Eastern Cooperative Oncology Group)Performance Status 0 or 1

- Ability to provide consent and comply with study protocol

- Women of child-bearing potential must have a negative pregnancy test and avoid
pregnancy during the study

Exclusion Criteria:

- Age < 18

- History of other malignancy in previous 2 years except carcinoma in situ of the cervix
or bladder, or non-melanoma skin cancer

- Previous chemotherapy or radiation therapy for pancreatic cancer or previous radiation
to the target field

- Clinically active autoimmune disease or active infection

- History of heart attack within 90 days or stroke within 6 months, hypertension
requiring change in blood pressure medications in the last 4 weeks, hypotension,
uncontrolled arrhythmias, heart failure (NYHA >= Class 2 in last 6 months), unstable
angina, or angina during sexual activity

- Use of nitrates or nitroglycerin

- History of hereditary degenerative retinal disorders including retinitis pigmentosa

- Chronic systemic corticosteroid use at supra-physiologic doses

- Use of recreational drugs called 'poppers' like amyl nitrite and butyl nitrite

- Blood test results (neutrophils < 1000 /uL (microliter); hemoglobin < 9 gm /dL;
platelet count < 1000 cells / uL; significant coagulopathy; significant liver or renal
dysfunction