Clinical Features of Neurotoxicity Following CD19 CAR T-cell Therapy in Mantle Cell Lymphoma.

CD19 chimeric antigen receptor (CAR) T-cell therapy has proven highly effective for treating relapsed/refractory mantle cell lymphoma (MCL). However, immune effector cell-associated neurotoxicity syndrome (ICANS) remains a significant concern. This study aimed to evaluate the clinical, radiological, and laboratory correlatives associated with ICANS development following CD19 CAR T-cell therapy in patients with MCL. All patients (n = 26) who received standard of care brexucabtagene autoleucel until July 2022 at our institution were evaluated. Laboratory and radiographic correlatives including brain magnetic resonance imaging (MRI) and electroencephalogram (EEG) were evaluated to determine the clinical impact of ICANS. Seventeen (65%) patients experienced ICANS after treatment, with a median onset on day 6. Ten (38%) patients experienced severe (≥ grade 3) ICANS. All ICANS patients had antecedent cytokine release syndrome (CRS), but no correlation was observed between ICANS severity and CRS grade. 92% of EEGs revealed interictal changes; no patients experienced frank seizures due to ICANS. 86% of severe ICANS patients with post-infusion brain MRIs demonstrated acute neuroimaging findings not seen on pretreatment MRI. Severe ICANS was also associated with higher rates of cytopenia, coagulopathy, increased cumulative steroid exposure, and prolonged hospitalization. However, severe ICANS did not affect treatment outcomes of patients with MCL. Severe ICANS is frequently associated with a range of post-infusion brain MRI changes and abnormal EEG findings. Longer hospitalization was observed in severe ICANS patients, especially those with abnormal acute MRI or EEG findings, but there was no discernible impact on overall treatment response and survival.