This study looks at a new treatment for pancreatic cancer using **Alpha DaRT** with chemotherapy. **Alpha DaRT** stands for "Diffusing Alpha-emitters Radiation Therapy," which is a type of radiation treatment. It's designed for people with pancreatic cancer that is either locally advanced or metastatic, meaning it has spread to other parts of the body. **Key Points**: - The study lasts about 6 months and involves treatment with **mFOLFIRINOX**, which is a combination of chemotherapy drugs, before using Alpha DaRT. - Participants will be divided into two groups based on their cancer's progression. **Cohort 1** will include patients with locally advanced cancer, and **Cohort 2** will include those with metastatic cancer. - The main goal is to see how safe Alpha DaRT is when used with chemotherapy and to check its effectiveness in controlling the cancer and pain. Participants must meet certain health criteria and agree not to become pregnant during the study and for three months after. The study is for adults 18 years and older, with a life expectancy of more than six months. Participants should not have previous treatments that could interfere with this study.