Persistent parkinsonism with dopaminergic denervation following axicabtagene ciloleucel therapy for diffuse large B cell lymphoma: a case report.

While immune effector cell-associated neurotoxicity syndrome (ICANS) remains one of the major adverse events in CD19-targeted CAR-T cell therapy, neurodegenerative-like movement disorders are characteristically associated with BCMA-targeted therapies, not CD19. We report a distinct case of persistent parkinsonism that became evident during recurrent neurological deterioration accompanied by a decline in ICE score in a patient treated with axicabtagene ciloleucel for relapsed diffuse large B cell lymphoma. Notably, 123I-Ioflupane SPECT revealed reduced striatal dopamine transporter uptake, consistent with nigrostriatal dopaminergic dysfunction. This case expands the neurological spectrum of CD19 CAR-T cell therapy and suggests that persistent parkinsonism may occur in temporal association with ICANS. Clinicians should be aware that persistent movement disorders may complicate the course of CD19 CAR-T cell therapy, warranting comprehensive imaging evaluation in patients with atypical neurological recovery.