Tumor infiltration therapy: from FDA approval to next-generation approaches

Tumor-infiltrating lymphocyte (TIL) therapy represents an emerging and promising approach in the field of cancer immunotherapy, harnessing the body's own immune cells to target and eliminate cancer cells. This review provides an in-depth analysis of TIL therapy, focusing on its mechanisms, clinical applications, challenges, and future prospects. TILs, particularly CD8 + T cells, are isolated from a patient's tumor, expanded ex vivo, and reinfused to promote anti-tumor immunity. The success of TIL therapy has been demonstrated in various cancers, particularly melanoma, where it has led to durable responses and, in some cases, complete remission. However, significant challenges remain, including the heterogeneity of TIL populations, difficulties in large-scale expansion, and immune-related adverse events. We also explore current strategies aimed at overcoming these limitations, including genetic modification of TILs, combinatory approaches with checkpoint inhibitors, and optimization of tumor infiltration protocols. With ongoing research and technological advancements, TIL therapy holds substantial promise as a cornerstone of personalized cancer treatment. This review synthesizes the current landscape of TIL therapy, providing insights into its clinical efficacy, potential for broader application, and the future of cancer immunotherapy.