Inclusion Criteria:  Histologically verified pancreatic adenocarcinoma, based on either a biopsy of the primary tumor or a metastasis One liver metastasis treatable by IRE (as determined by MDT at Aalborg University Hospital) One tumor lesion suited for repeated biopsy by transcutaneous core needle (preferably another lesion than that used for IRE) At least one measurable lesion (RECIST version 1.1) other than the liver metastasis to be treated by IRE At least one course of chemotherapy for metastatic or inoperable disease discontinued due to treatment failure or intolerance Performance status 0-1 ASA ≤ 3 ≥ 18 years of age Written and orally informed consent Sufficient available histological tumor material stored in biobank or obtainable by new biopsy Patient acceptance of collection of blood samples for translational research and two additional biopsies during treatment  Adequate bone marrow function, liver function, and renal function (within 7 days prior to enrollment):  Neutrophils (ANC) ≥ 1.5 x 109/l Platelet count ≥ 100 x 109/l Hemoglobin ≥ 6 mmol/l Plasma bilirubin ≤ 1.5 x ULN Plasma alanine transaminase (ALAT) < 5 x ULN Plasma creatinine ≤ 1.5 x ULN INR ≤ 1.5  Exclusion Criteria:  Underlying medical disease not adequately treated (e.g. poorly regulated diabetes and symptomatic cardiac disease) Prior or current autoimmune disorder with risk of serious toxicity during treatment with checkpoint inhibitor Acute myocardial infarction, cerebral vascular attack, transient ischemic attack or subarachnoid hemorrhage within 6 months from start of treatment Previous reception of allogeneic stem cells or solid organ donation Active infection requiring systemic therapy within 7 days prior to treatment initiation Positive HIV, HBV, and HCV test results (prior testing or new testing in patients at risk) Active psychiatric disease or history of drug or alcohol abuse affecting participation Allergy to active substance or any of the auxiliary agents, including known severe allergy to anesthetic agent, paralytic agent or any of the equipment used during treatment Expected need for systemic corticosteroid or other systemic immunosuppressive drug during the course of this clinical trial. A low dose of e.g. prednisone ≤ 10 mg/day is permitted for maximally 7 consecutive days Coexisting malignant disease, except non-melanoma skin cancer Symptomatic or untreated CNS metastases Liver cirrhosis Child Pugh >A Pregnant or breast-feeding patients. For women of childbearing potential, a negative pregnancy test (minimum sensitivity 25mIU(hCG)/ml) is mandatory prior to inclusion and every month during the trial Women of childbearing potential not willing to use effective methods of contraception during treatment and for 6 months after the end of treatment. Male patients with a fertile partner are also required to secure effective methods of contraception (definition available in protocol) Previous immunotherapy Patients referred from a hospital outside of Denmark Major dilation of veins or bowel obstructing the needle path Persistent atrial fibrillation Metal objects (e.g. biliary SEMS) within 5 cm of ablation target Cardiac pacemaker or ICD, that cannot be safely disconnected during IRE treatment