Eligibility Criteria:
Inclusion Criteria:
* Written informed consent before beginning any protocol specified procedures
* Histologically proven pancreatic adenocarcinoma
* Any T, any N, M0 disease that has had all gross disease resected (R0 or R1 resection)
* ECOG Performance status index 0 or 1
* Absolute Neutrophils \>= 1.5 x 10\^9/L
* Platelets \>= 100 x 10\^9/L
* Hemoglobin \>= 10 g/dL
* Total bilirubin =\< 2.0 x UNL; subjects with Gilbert's syndrome, confirmed by genotyping or invader UGTIA1 molecular assay before study entry must have total bilirubin \< 3 x UNL
* ASAT (SGOT) and ALAT (SGPT) =\< 2.5 x UNL
* Alkaline Phosphatase =\< 5 x UNL
* Creatinine \< 1.5 x UNL
* Serum Na, K+, Magnesium, Phosphate and Calcium \>= LNL
* First study treatment must be given within 60 days after surgery and within 7 days after randomization
* Patients must be accessible for treatment and follow-up and compliant with study procedures
* Negative pregnancy test (urine or serum) within 7 days before first study treatment for all women of childbearing potential, whom also must implement adequate non-hormonal contraceptive measures during study treatment and for at least 3 months after the last dose of study therapy
* Ability to take oral medication (dasatinib must be swallowed whole)
Exclusion Criteria:
* Prior or concurrent systemic anticancer therapy (immunotherapy, hormonal therapy, biological therapy, or chemotherapy) for pancreatic cancer
* Prior or concurrent radiation therapy for pancreatic cancer
* Pregnant or lactating patients
* M1 pancreatic cancer
* Concurrent congestive heart failure, unstable angina pectoris, or M1 within the 6 months before first study treatment
* Uncontrolled hypertension or high-risk uncontrolled arrhythmias
* Any history of clinically significant ventricular arrhythmias (such as ventricular tachycardia, ventricular fibrillation, or torsades de pointes)
* Diagnosed or suspected congenital long QT syndrome
* Prolonged QTc interval on pre-entry electrocardiogram (\> 450 msec)
* History of significant neurologic or psychiatric disorders including psychotic disorders, dementia or seizures that would prohibit the understanding and giving of informed consent
* Past or current history of neoplasm other than pancreatic adenocarcinoma, except for: curatively treated non-melanoma skin cancer; in situ carcinoma of the cervix; other cancer curatively treated and with no evidences of disease for at least 1 year
* Concurrent treatment with other experimental drugs or treatment with investigational drugs within 30 days of first study treatment
* Currently receiving drugs with known significant CYP 3A4 inhibitory effects (such as ketoconazole, itraconazole, troleandomycin, erythromycin, diltiazem, verapamil, ritonavir, indinavir)
* Concurrent administration with inducers of CYP 3A4 may result in a lower exposure to dasatinib and are therefore not allowed (e.g., phenytoin, carbamazepine, rifampicin, phenobarbital, pentobarbital, or St John's Wort)
* Known allergy reactions to dasatinib or gemcitabine or excipients used in the study
* History of significant bleeding disorders unrelated to cancer, including: diagnosed congenital bleeding disorders (e.g., Von Willebrand's disease); diagnosed acquired bleeding disorder within 1 year (e.g., acquired anti-factor VIII antibodies); ongoing or recent (=\< 3 months) significant gastrointestinal bleeding
* Patients currently taking drugs that are generally accepted to have a risk of causing Torsades De Pointes including: quinidine, procainamide, disopyramide; amiodarone, sotalol, ibutilide, dofetilide; erythromycins, clarithromycin; chlorpromazine, haloperidol, mesoridazine, thioridazine, pimozide; cisapride, bepridil, droperidol, methadone, arsenic, chloroquine, domperidone, halofantrine, levomethadyl, pentamidine, sparfloxacin, lidoflazine
* Concurrent treatment with intravenous bisphosphonates; prior treatment should be stopped at least 2 weeks before first dose of study treatment
* Concurrent medical condition which may increase the risk of toxicity, including pleural or pericardial effusion or any grade
* Active uncontrolled infection requiring parenteral antimicrobials