Chimeric Antigen Receptor T-Cell Therapy and Imaging Applications for Large B-Cell Lymphoma

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment of large B-cell lymphoma (LBCL) and other hematologic malignancies. Its mechanism of action relies on recent biotechnological advances that allow clinicians to harness and enhance a patient's immune system to fight cancerous cells. The indications for CAR T-cell therapy continue to expand, with ongoing trials evaluating their use in other hematologic and solid organ malignancies. This review explores the vital role of diagnostic imaging in patient selection and treatment response in CAR T-cell therapy for LBCL and the management of specific therapy-related adverse events. For a patient-centered and cost-effective use of CAR T-cell therapy, it is crucial to select patients who are likely to derive long-term benefit and optimize their care during a lengthy treatment pathway. Metabolic tumor volume and kinetics assessed at PET/CT have emerged as powerful tools to predict outcome after CAR T-cell therapy in LBCL, allowing for the early identification of lesions refractory to treatment and identification of the severity of CAR T-cell therapy toxicity. Radiologists should be aware that the success of CAR T-cell therapy is mitigated by adverse events, most importantly neurotoxicity, which remains poorly understood and challenging to treat. Neuroimaging, with experienced clinical evaluation, is critical in the diagnosis and management of neurotoxicity and the exclusion of other central nervous system complications that can occur in this clinically vulnerable patient group. This review discusses current applications of imaging in the standard CAR T-cell therapy pathway for the treatment of LBCL, which serves as a model disease in the integration of diagnostic imaging and radiomic risk markers.