Researchers are looking for better ways of understanding and treating pancreatic cancer. The purpose of this study is to see how useful it is to look for changes and characteristics in your genes (molecules that contain instructions for the development and functioning of the cells) and the genes within the tumour. These characteristics may be useful in choosing treatments for patients in the future. Changes (mutations) in genes have been shown to be an important characteristic in cancers. Looking at differences in genes in patients with advanced pancreatic ductal adenocarcinomas and comparing this information with response to their initial chemotherapy treatment may help to learn which treatments may be better for certain patients after initial treatment.

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.

Locally advanced or metastatic pancreatic ductal adenocarcinoma