Cell- and antibody-based therapies, including chimeric antigen receptor T-cell (CAR-T) therapy and bispecific antibodies, represent significant advances in the treatment of hematologic malignancies. These therapies optimise the patient's immune system to target and eliminate malignant cells, achieving profound and durable responses in patients where conventional treatment approaches have failed. However, their mechanism of action-through profound immune activation-introduces a challenging toxicity profile, including cytokine release syndrome and immune effector cell-induced neurotoxicity. Emerging evidence suggests that neurotoxicity associated with these therapies may extend beyond acute symptoms to include persistent cognitive impairments. Such impairments can manifest deficits in memory, attention, executive functioning, and processing speed, potentially compromising patients' quality of life, ability to manage daily activities and return to work.

The COGNITOX project explores the occurrence, clinical manifestations, and impact on quality of life of neuro-psychologically assessed and patient-reported cognitive impairment. The project's data set is generated through standardized neuropsychological tests (recommended by the International Cognition and Cancer) and validated patient reported outcome measures, to evaluate multiple cognitive domains. The project is developed in close collaboration between the Department of Haematology, Aarhus University Hospital and the Unit for Psychooncology and Health Psychology (EPoS), Department of Psychology and Behavioural Sciences, Aarhus University.

The current literature on cognitive impairment secondary to cell- and antibody-based therapies is limited, and none of the studies reported so far were conducted within a Danish healthcare context. Understanding the prevalence, severity, and functional impact of cognitive impairments in this patient population is critical. These insights will inform clinical practice, guide patient counseling, and support the development of targeted interventions aimed at mitigating cognitive decline. By generating robust data, this project seeks to improve the knowledge within the field and lay the foundation for an intervention study addressing the needs of patients undergoing these advanced immunotherapies.

Inclusion Criteria:

• Patients must be ≥ 18 years old
• Able to speak and read Danish
• Provide informed consent

Exclusion Criteria:

• CNS-involvement by the haematological malignancy
• Cognitive impairment due to pre-existing psychiatric or neurological conditions

Patients diagnosed with a malignant haematological disease at the Department of Haematology, Aarhus University Hospital will be enrolled according to the above mentioned treatment subsets and pre-defined inclusion criteria.