Step 1: patients will sign a 1st informed consent prospectively for the molecular screening (RNAseq profile). 5 transcriptomic signatures will be applied for prediction of response to 5 Fluoro-Uracil (5FU), oxaliplatin, irinotecan, gemcitabine and taxane. Biomarker status will be obtained for all patients as part of good clinical practice.~Patients will be eligible for prospective step 2 only if the transcriptomic analysis is informative and the treatment can be started within 28 days.~Step 2: study treatment strategy: based on the results of transcriptomic signatures, patients will receive either FOLFIRINOX or Gem-nabP according to the following algorithm (2nd informed consent):~Predicted to be FOLFIRINOX sensitive (regardless of sensitivity to Gem-nabP) = FOLFIRINOX~Predicted to be FOLFIRINOX and Gem-nabP resistant = FOLFIRINOX~Presence of a germline breast cancer (BRCA) mutation (regardless of transcriptomic signature) = FOLFIRINOX (tumors sensitive to platinum).~Predicted to be Gem-nabP sensitive and FOLFIRINOX resistant = Gem-nabP~Chemotherapy with FOLFIRINOX and Gemcitabine plus nab-paclitaxel will be administered as in routine practice, according to their approval. Dose adaptation will be allowed according to investigator's usual practice.
The aim of this study is to assess the clinical value of 5 transcriptomic signatures prognostic of chemotherapeutic sensitivity to improve the Objective Response Rate (ORR) of first-line (L1). Chemotherapy regimen (FOLFIRINOX vs Gem-nabP) will be selected based on transcriptomic signatures applied to the pre-therapeutic liver biopsy of newly diagnosed PDAC patients.