CAR-T Cell Therapy in Gastrointestinal Surgical Oncology: Expanding Horizons beyond Hematologic Malignancies.

Introduction
The introduction of chimeric antigen receptor T-cell (CAR-T) therapy has revolutionized hematologic oncology, particularly in B-cell acute lymphoblastic leukemia and diffuse large B-cell lymphoma, where durable remissions have been achieved even in relapsed or refractory cases (1). Building on this unprecedented success, researchers have sought to extend CAR-T therapy to solid tumors. Gastrointestinal (GI) cancers, however, pose unique challenges. These include dense stromal barriers, an immunosuppressive tumor microenvironment (TME), heterogeneous antigen expression, and difficulties in ensuring adequate trafficking of effector T-cells (2,3). From the standpoint of a gastrointestinal cancer surgeon, the perioperative integration of CAR-T into multimodal strategies offers a compelling opportunity to enhance its translational potential and reshape GI oncology practice (4).