Frontal predominant encephalopathy with early paligraphia as a distinctive signature of CAR T-cell therapy-related neurotoxicity

Chimeric antigen receptor (CAR) T-cell therapy is an emerging highly effective treatment for refractory haematological malignancies. Unfortunately, its therapeutic benefit may be hampered by treatment-related toxicities, including neurotoxicity. Early aggressive treatment is paramount to prevent neurological sequelae, yet it potentially interferes with the anti-cancer action of CAR T-cells. We describe four CAR T-cells infused patients who presented with reiterative writing behaviours, namely paligraphia, as an early manifestation of neurotoxicity, and eventually developed frontal predominant encephalopathy (one mild, three severe). Paligraphia may represent an early, specific, and easily detectable clinical finding of CAR T-cell therapy-related neurotoxicity, potentially informing its management.