A Hypothesis for Organ-Preserving Immunotherapy in Pancreatic Tail Cancer with Splenic Metastasis

Background: The standard treatment for pancreatic tail cancer with splenic metastasis is distal pancreatectomy with splenectomy (DPS), which removes the largest lymphoid organ and interrupts immune trafficking from the spleen via the splenic vein to the pancreas. Hypothesis: Splenic metastases serve as a Pure Antigen Reservoir (PAR). Injection of sterile water into the metastatic focus induces hypotonic lysis, releasing tumor antigens and DAMPs. Sustained mild hyperthermia (39°C) enhances vascular permeability, adhesion molecule expression, and T-cell homing. Effector T cells return to the pancreatic tail via the splenic vein (venous route) and retrograde lymphatic clearance (lymphatic route). Clinical evidence shows that splenic vein involvement predicts early liver metastasis—a pathway currently ligated by DPS but preserved under my hypothesis. Proposed Workflow: A closed-loop design incorporates a Day-3 decision point: non-responders return to Day 1 for complete re-induction. Conclusion: This strategy preserves both organs, uses routine clinical resources, and carries no drug toxicity. I call for clinical investigation to validate this hypothesis.