Neurocognitive Outcomes over the First 3 Months after Chimeric Antigen Receptor T-Cell (CAR T) Therapy: Preliminary Findings from a Longitudinal Study

Introduction People treated with systemic therapies for cancer may exhibit changes in neurocognitive functioning over time, affecting domains such as memory, processing speed, and executive functioning. There is a need for prospective data regarding neurocognitive outcomes among patients treated with Chimeric Antigen Receptor T-Cell (CAR T) therapy. The purpose of this study was to investigate the trajectory of neurocognitive performance and self-reported cognitive functioning over the first 3 months of CAR T therapy. Methods As part of a larger cohort study of patients treated with CAR T, neurocognitive outcomes were assessed prior to starting CAR T and again at 1- and 3- months post-CAR T. Neurocognitive performance was measured using standardized neuropsychological tests including measures of verbal memory (Hopkins Verbal Learning Test-Revised (HVLT-R) - immediate recall, delayed recall, retention), processing speed (Trail-making Test - Part A (TMT-A)) and executive functioning (Trail-making Test Part B (TMT-B), Controlled Oral Word Association Test (COWAT)). Raw test scores were converted to z-scores (Mean 0, SD 1) based on norms adjusted for age, sex, and education, where applicable. Impairment on individual tests was defined by a z score ≤ -1.64. Participants were categorized as showing overall impairment if they had at least two tests with a z-score of ≤ -1.5 or a z-score ≤ -2.0 on one test. Self-reported cognitive functioning was measured using the Functional Assessment of Cancer Therapy - Cognition, Perceived Cognitive Impairment score (FACT-Cog3 PCI) and the European Organisation for Research and Treatment of Cancer - Quality of Life Questionnaire C-30, Cognitive Functioning scale (EORTC QLQ-C30 CF). Demographic and clinical data were collected through self-report and patient records. Frequencies of impairment were determined at each time point, with clinically significant changes on individual test scores in the first month determined based on z-score changes of ≥1.0 or minimal clinically important differences for self-report questionnaires. Linear mixed models were generated to estimate the trajectory of neurocognitive performance and self-reported cognitive functioning over time from baseline to 3 months. Results Neurocognitive outcomes were available for 37 participants at baseline, with follow-up data available for 29 patients at 1 month and 17 patients at 3 months. Participants were 54% male, had a mean age 58.4 years (sd 11.3) and a mean 1