The purpose of this study is to evaluate the clinical safety and efficacy of Gemcitabine plus nab-Paclitaxel chemoradiotherapy and to determine the Maximal Tolerated Dose (MTD) for unresectable locally advanced pancreatic adenocarcinoma.

Gemcitabine plus nab-Paclitaxel is one of the standard chemotherapy for metastatic pancreatic adenocarcinoma. Gemcitabine plus nab-Paclitaxel realize the favorable anti-tumor effect and tolerable toxicity. Gemcitabine plus nab-Paclitaxel is a promising regimen for concurrent chemoradiotherapy, but the investigators need to know the safety in the case of the concurrent chemoradiotherapy.

Inclusion Criteria:

• Histologically or cytologically confirmed advanced pancreatic cancer

• Locally advanced pancreatic cancer is defined as the presence of a surgically unresectable tumor(involving the celiac axis or the superior mesenteric artery)

• Performance Status:0-1(ECOG)

• Patients of age =>20 and 75>

• White Blood Cell (WBC) >=3,500/mm3,12,000/mm3,

  • Neutrophils >=1,500/mm3, platelets=100,000/mm3,
  • Hemoglobin >=9.5 g/dl,
  • GOT </=2.0 X Upper Limit Number (ULN),
  • Glutamate Pyruvate Transaminase (GPT) </=2.0 X ULN,
  • Alkaline Phosphatase (ALP) </=2.0 X ULN,
  • Total bilirubin <=1.5mg/dl,
  • Serum creatinine <=1.2mg/dl,
  • Creatinine clearance>=50 ml/min
  • arterial O2 pressure (PaO2) >=70torr or arterial O2 saturation (SpO2) >=96%

• Life expectancy more than 3 months.

• Written informed consent.

Exclusion Criteria:

• Active infection
• Lung fibrosis or intestinal pneumonia detectable on chest X-ray and CT
• Severe complication (heart disease, cirrhosis, diabetes)
• Myocardial infarction within 3 months
• Active synchronous or metachronous malignancy
• Pregnant or lactation women, or women with known or suspected pregnancy
• Symptomatic brain metastasis
• History of severe drug allergy
• Peripheral neuropathy
• Patients who are judged inappropriate for the entry into the study by the investigator