GTX-RT in Borderline Resectable Pancreatic Cancer

Inclusion Criteria: * Patients must have histologically or cytologically confirmed pancreatic adenocarcinoma that is borderline resectable disease. Borderline resectable lesions are defined as: * circumferential tumor abutment with the superior mesenteric vein (SMV) or portal vein (PV) or SMV/PV confluence over \</= 180° * circumferential tumor abutment with the superior mesenteric artery (SMA) over \</= 180° * Short segment encasement (360°) of the PV or SMV that is amenable to partial vein resection and reconstruction * encasement of the gastroduodenal artery up to the origin of the hepatic artery * Patients must have measurable disease * No previous chemotherapy or radiation to the pancreas * Eastern Cooperative Oncology Group (ECOG) performance status \</= 2 (Karnofsky \>/= 60%) * Patients must have normal organ and marrow function as defined below: * leukocytes \>/= 3,000/μL * absolute neutrophil count \>/= 1,000/ μL * platelets \>/= 100,000/ μL * creatinine within normal institutional limits (ULN) * total bilirubin will allow for 2x the upper limit of the institution. Patients may have biliary stents or drains to lower total bilirubin to this range. * Has a negative serum or urine pregnancy test within 7 days prior to initiation of therapy (female patients of childbearing potential). Postmenopausal women must have been amenorrheic for at least 12 months to be considered of non-childbearing potential. Patients will agree to continue contraception for 30 days from the date of the last study drug administration. * Ability to understand and the willingness to sign a written informed consent document Exclusion Criteria: * Patients with metastatic disease are ineligible. * Patients who have had prior chemotherapy for pancreatic adenocarcinoma * Patients who have received prior radiation to an abdominal site are not eligible. * Patients with peripheral neuropathy \>/= grade 2 * Patients with a history of severe hypersensitivity reaction to Taxotere (docetaxel), other drugs formulated with polysorbate 80, gemcitabine, or capecitabine * Patients may not be receiving any other investigational agents. * ECOG Performance Status 3-4 * Pregnant or breast-feeding women are excluded from this study because gemcitabine,capecitabine, and docetaxel are Class D agents with the potential for teratogenic or abortifacient effects. * Uncontrolled intercurrent illness including, but not limited to, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * Patients must not have any comorbid inflammatory conditions of the bowel such as Crohn's Disease.