Study of Changes and Characteristics of Genes in Patients With Pancreatic Cancer for Better Treatment Selection

Inclusion Criteria:

* Patients must have a histological or radiological diagnosis of locally advanced or metastatic pancreatic ductal adenocarcinoma. Patients with borderline resectable disease are not eligible.
* Patient must have a tumor lesion that is amenable to a core needle biopsy.
* Patients must have a measurable lesion by RECIST 1.1 in addition to the lesion that is going to be biopsied.
* Patients must be fit enough to safely undergo a tumor biopsy.
* Age 18 years or older.
* Eastern Cooperative Group (ECOG) performance status of 1 or less.
* Life expectancy of greater than 90 days.
* Patients must have normal organ and marrow function
* Patients must undergo systemic treatment with m-FOLFIRINOX or nab-paclitaxel as a first line standard systemic palliative treatment or combination treatment with m-FOLFIRINOX or nab-paclitaxel with or without other investigational agents within a clinical trial as a first line palliative treatment.
* Ability to understand and willing to sign a written informed consent document.

Exclusion Criteria:

* Patients with one or more contraindications to tumor biopsy.
* Patients who have prior systemic treatment (chemotherapy or any other anti-cancer agent) in advanced setting.
* Patients who are currently on anti-cancer treatment including chemotherapy.
* Patients with known brain metastases.
* Patients with advanced PDAC who are going to be treated with gemcitabine monotherapy in advanced setting.
* Uncontrolled inter-current illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
* Any other condition that would, in the Investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns or compliance with clinical study procedures.