Clinical Reasoning: Assessing New Neurologic Deficits in Patients with Hematologic Malignancy on Bruton Tyrosine Kinase Inhibitor Therapy

Patients with cancer can develop neurologic deficits that frequently, but not exclusively, arise from intracranial involvement by malignancy. In this case series, we highlight 3 patients with new focal neurologic deficits in the setting of hematologic cancers without baseline intracranial disease. The first, with Waldenstrom macroglobulinemia, develops bradyphrenia, inattention, and disorientation. Patients 2 and 3 have diagnoses of chronic lymphocytic leukemia (CLL), with one experiencing a first lifetime seizure and the other right hemiparesis, rash, headache, and intermittent speech arrest. A description of the pathophysiology of the final diagnosis, suggestive imaging characteristics, and historical outcomes follows to improve future diagnostic precision.