Gemcitabine Pharmacokinetics After Preoperative Chemoradiation Therapy

Inclusion Criteria:

1. Cytologic or histologic proof of adenocarcinoma of the pancreas is required. Patients with Islet cell tumors are not eligible.
2. Patients do not have known metastases.
3. Patients must have potentially resectable or borderline resectable pancreatic cancer and have agreed to undergo surgical resection at MD Anderson Cancer Center if operable. They will have undergone staging (physical examination, chest x-ray, contrast enhanced CT or MRI (if CT contraindicated) and/or angiogram) to determine resectability.
4. Patients have completed radiation and chemotherapy with either fluoropyrimidines (5-FU or capecitabine) or gemcitabine as a radiosensitizing agent as part of their preoperative therapy. Previous systemic chemotherapy alone is not allowed. Preoperative therapy will be completed at least 4 weeks prior to surgery.
5. Patients with Karnofsky performance status \> 70 are eligible.
6. There will be no upper age restriction. Patients less than 18 years of age are excluded from the protocol because adenocarcinoma of the pancreas is rarely seen in the pediatric population.
7. Adequate renal and bone marrow function: Leukocytes \>= 3,000/uL; Absolute neutrophil count \>= 1,500/uL; Platelets \>= 100,000/Ul; Serum creatinine \<= 2.0 mg/dL; Creatinine clearance \>= 60 ml/min (calculated by the Cockcroft -Gault equation)
8. Adequate Hepatic function (endoscopic or percutaneous drainage as needed): Total bilirubin \< = 3 X institutional upper limits of normal (ULN); AST (SGOT)/ALT (SGPT) \<= 5 X institutional ULN
9. Patients must have no fever or evidence of infection or other coexisting medical condition that would preclude administration of gemcitabine. Patients with uncontrolled congestive heart failure, unstable angina and myocardial infarction within 3 months will be excluded.
10. Patient is not pregnant. Women of childbearing potential (i.e., women who are pre-menopausal or not surgically sterile) must use acceptable contraceptive methods (abstinence, intrauterine device \[IUD\], oral contraceptive or double barrier device) and refrain from breast-feeding, as specified in the informed consent.
11. Patients must sign a study-specific consent form.

Exclusion Criteria:

1. Major cardiovascular or pulmonary comorbidity that precludes use of general anesthesia (NYHA \[New York Heart Association\] Class III and IV).
2. Identification of metastatic disease.
3. Patients with a known hypersensitivity to Gemcitabine.
4. Pregnant women
5. Inability to comply with study and/or follow-up procedures.
6. Patients \< 18 years of age.