A comprehensive review maps how CAR-T cell therapy has moved beyond blood cancers, documenting approvals and new indications while also summarizing where solid tumor and autoimmune attempts are still constrained. It highlights that multiple CAR-T products have received U.S. approval by the end of 2024, while ongoing work seeks to improve persistence, trafficking, and target engagement in solid tumors. For the field, the report is a practical status check: it inventories where the modality is progressing and where immunologic barriers continue to limit results. The synthesis also reinforces that engineering changes—such as persistence controls and tumor microenvironment tuning—remain the central lever for next-generation CAR-T programs.