Assessing Cognitive Function in Transplantation and CAR-T Recipients: Expert Recommendations from the Survivorship, Aging and Biobehavioral Special Interest Groups of ASTCT.

Abstract

Cognitive impairment is a prevalent yet underexplored comorbidity and complication in hematopoietic stem cell transplantation (HCT) and chimeric antigen receptor (CAR) T-cell therapy. Affecting up to half of patients, cognitive impairment may include acute phases, manifesting as transplant-associated altered mentation and encephalopathy (TAME) or immune effector cell-associated neurotoxicity syndrome (ICANS), and may persist for years post-treatment as cancer-related cognitive impairment (CRCI). Such dysfunction undermines autonomy, healthcare management, work reintegration, and quality of life. This consensus review synthesizes current evidence on CRCI across the timeline of transplant and cellular therapy, organized into pre-, peri-, and post-therapy phases, with additional focus on specific populations, such as older adults and pediatric patients. It highlights gaps in understanding of cognitive impairment risks, trajectory, and impact, alongside the challenges of standardizing assessments in diverse practice settings. Key recommendations, endorsed by the American Society for Transplantation and Cellular Therapy (ASTCT) Aging, Biobehavioral Research, and Survivorship Special Interest Groups, advocate for cognitive assessment pre- and post-therapy using validated instruments, like the Montreal Cognitive Assessment (MoCA) or Blessed Orientation-Memory-Concentration Test (BOMC). We additionally recommend supplementing with patient-reported outcomes (PROs) measures for comprehensive evaluation. If cognitive impairment is identified, we recommend action items, including exclusion of alternative etiologies, reconsideration of therapy or caregiving plan, and referrals for additional evaluation and rehabilitation, among others. Practical guidance for implementation across clinical and research settings is provided, emphasizing the need for multidisciplinary strategies to address identified impairments. This work aims to establish a framework for systematic cognitive monitoring, improving patient outcomes and quality of life while guiding future research to address significant knowledge and implementation gaps.