Clinically suspected central nervous system Richter transformation presenting with progressive psychiatric symptoms: A case report.

Background: Central nervous system (CNS) involvement associated with Richter transformation (RT) is a rare complication of chronic lymphocytic leukemia (CLL). Neurological manifestations are heterogeneous. To our knowledge, no previous reports have described CNS RT presenting predominantly with psychiatric and behavioral symptoms. We report a clinically suspected case of CNS RT presenting predominantly with progressive psychiatric symptoms in the presence of extensive CNS lesions but without apparent focal neurological deficits. Case Presentation: A 71-year-old man with no psychiatric history developed progressive personality change, irritability, emotional lability, behavioral disinhibition, and sleep-wake cycle disturbance. Gadolinium-enhanced fluid-attenuated inversion recovery magnetic resonance imaging demonstrated newly developed multifocal lesions predominantly involving the bilateral temporal lobes. Hematological evaluation established previously unrecognized CLL. Although histopathological confirmation was not obtained, the overall clinical, radiological, and laboratory findings supported CNS involvement associated with clinically suspected RT as the most likely diagnosis. Progressive neuropsychiatric deterioration limited invasive diagnostic procedures and disease-directed treatment. Supportive and palliative management was provided, and the patient died of aspiration pneumonia 114 days after surgery. Conclusion: This case demonstrates that clinically suspected CNS RT may present predominantly with progressive psychiatric and behavioral symptoms in the absence of focal neurological deficits. Severe neuropsychiatric symptoms may themselves impede diagnostic confirmation and disease-directed treatment. When pathological confirmation is not feasible, multidisciplinary discussion and shared decision-making with the patient and family, together with explicit acknowledgment of diagnostic uncertainty and careful balancing of the benefits and burdens of further investigation and treatment, may support patient-centered care.