Study Summary: This clinical trial is researching a new treatment for advanced pancreatic ductal adenocarcinoma (PDAC), a type of cancer. The treatment uses special cells called CAR-NK cells, which are designed to target and kill cancer cells. These cells are engineered to recognize and attack specific proteins found on cancer cells, known as antigens. There are two groups in the study, based on the type of antigens present in the patient's tumor.

• **Study Length:** Participation may involve up to 3 infusions and regular check-ups every 8 weeks.
• **Safety Monitoring:** Close observation for side effects like infusion reactions and neurotoxicity.
• **Eligibility:** Patients must be 18-75 years old with a confirmed diagnosis of PDAC and meet other health criteria.

This study assesses if the treatment is safe and how well it works. Participants will receive chemotherapy to prepare their bodies before being given the CAR-NK cells. Doctors will monitor for any side effects and measure if the cancer responds to the treatment using imaging tests. Participation is voluntary and requires informed consent.