Utility of neurotoxicity investigations in CD19 and BCMA CART recipients with ICANS

In grade 1 ICANS, positive findings were infrequent (3% of grade 1), with relevant findings only observed on MRI. Our findings suggest brain MRI is useful for low-grade ICANS evaluation, but CSF analysis and EEG have low diagnostic yields. Immune effector cell-associated neurotoxicity syndrome (ICANS) is a potentially life-threatening toxicity of chimeric antigen receptor T-cell (CART) therapy, graded according to ASTCT consensus guidelines. Patients with suspected ICANS are evaluated with neurodiagnostic testing, including cerebrospinal fluid (CSF) analysis, magnetic resonance imaging (MRI), and electroencephalogram (EEG) to establish ICANS grade and to evaluate alternate causes of symptoms. The study aims to determine the diagnostic yield of this testing for identifying alternative causes of altered mental status or in grading ICANS. This study is a retrospective review of 347 adult patients with B-cell acute lymphoblastic leukemia (B-ALL), non-Hodgkin lymphoma (NHL), and multiple myeloma (MM) who received commercial or investigational CART targeting CD19 or BCMA at The University of Kansas Medical Center (KUMC) from December 2017 through November 2023. Of the 347 patients who received CART, 142 (41%) developed ICANS of any grade. Brain MRI identified alternative causes of neurologic symptoms in 13 (11%) patients. CSF analysis changed diagnosis in only 1 patient (1%) and no seizures were detected by EEG. These results suggest that brain MRI may assist with evaluation of ICANS, whereas EEG and CSF sampling rarely change diagnosis or alter clinical management.