Neurological and Cognitive Dysfunction Following CAR-T Treatment. ICANS and Beyond

This is a phase 4 non-interventional single center trial. We aim to prospectively include patients scheduled to undergo CAR-T therapy at ME CAST, Karolinska University Hospital Huddinge, to study ICANS. Because ICANS develops rapidly, inclusion during this potentially life-threatening phase would not be feasible; patients must therefore be enrolled before they start treatment. We aim to include patients who are clinically at high risk of developing ICANS. The risk of ICANS is assessed based on diagnosis, tumor burden, CAR-T product, and inflammatory status prior to treatment initiation. We plan to compare patients who develop ICANS grade 2-4 with patients who develop no ICANS or at most grade 1. Patients will undergo Positron Emission Tomography (PET) with two different tracers: (1) PBR28 for TSPO, which provides a measure of brain inflammation-this ligand binds to microglial cells-and (2) 11C-UCB-J for SV2A, which provides a measure of synaptic density in the brain. The results will be compared with magnetic resonance imaging. We will collect blood, bone marrow and cerebrospinal fluid (CSF) samples from this patient cohort. Samples will be taken from all patients before, during, and after CAR-T treatment. Participation in the study also includes computer-based cognitive testing, neuropsychological evaluation and genetic testing to determine whether the patient has receptors allowing binding of the TSPO radioligand used during PET imaging.