Biological Effect of Nab-paclitaxel Combined to Gemcitabine in Metastatic Pancreatic Cancer

Inclusion Criteria: 1. Age \> 18 years 2. Suspicion of pancreatic adenocarcinoma 3. With liver measurable metastases 4. Primary tumor non resected 5. First line systemic treatment 6. Correct haematological parameters 7. Adequate Blood chemistry levels 8. Life expectancy ≥ 2 months 9. PS: 0 - 2 10. Affiliation to French National social security or beneficiary 11. Signed informed consent. 12. Female patients must be surgically sterile, or be postmenopausal, or must commit to using reliable and appropriate methods of contraception during the study and during at least three months after the end of study treatment. All female patients with reproductive potential must have a negative pregnancy test (β HCG) within 72 hours prior to starting abraxane treatment. Breastfeeding is not allowed. Male patients must agree to use effective contraception in addition to having their partner use a contraceptive method as well during the trial and during at least six months after the end of the study treatment, Exclusion Criteria: 1. Previous radiotherapy of the tumor 2. Patient has only locally advanced disease. 3. Previous treatment with gemcitabine 4. Active infection or severe concomitant disease 5. Serious Peripheral neuropathy 6. Known hypersensitivity or contraindication to any component of study drug formulation. 7. Pregnant or breastfeeding women 8. Other experimental treatment 9. History of malignancy in the last 5 years. Patients with prior history of in situ cancer or basal or squamous cell skin cancer are eligible. Patients with other malignancies are eligible if they were cured by surgery alone or surgery plus radiotherapy and have been continuously disease-free for at least 5 years. 10. Known brain metastases, unless previously treated and well-controlled for at least 3 months (defined as clinically stable, no edema, no steroids and stable in 2 scans at least 4 weeks apart). 11. Patient has serious medical risk factors involving any of the major organ systems, or serious psychiatric disorders, which could compromise the patient's safety or the study data integrity 12. Patient with a history of interstitial lung disease, history of slowly progressive dyspnea and unproductive cough, sarcoidosis, silicosis, idiopathic pulmonary fibrosis, pulmonary, Hypersensitivity pneumonitis or multiple allergies 13. Patient uses Coumadin 14. Legal incapacity or limited legal capacity. Medical or psychological conditions not allowing the subject to complete the study or sign the consent.