Extensive Central Nervous System Lymphoma Detected at the Time of Diagnosis of Chronic Lymphocytic Leukemia - An Isolated Central Nervous System Richter’s Syndrome: A Case Report

Abstract

When a central nervous system (CNS) lesion is found in patients with chronic lymphocytic leukemia (CLL), the diagnostic possibilities include CNS involvement of CLL, transformation to a large B-cell lymphoma (Richter’s syndrome [RS]), or the coincidental presence of another tumorous or non-tumorous disease. CNS RS commonly occurs in preexisting CLL with other nodal/extra-nodal involvement, but it is extremely rare to find isolated CNS RS concurrently with the initial diagnosis of CLL. A 73-year-old woman presented with a headache and findings from another hospital of an elevated white blood cell count and intraventricular masses. A peripheral blood smear and a bone marrow biopsy revealed CLL. Brain magnetic resonance imaging with gadolinium enhancement showed a suprasellar mass and a pineal mass within the third ventricle, as well as extensive leptomeningeal enhancement. Whole-body fluorodeoxyglucose proton emission tomography-computed tomography showed no hot uptake except for the brain lesions. Cerebrospinal fluid cytology showed small atypical lymphocytes suggestive of CLL involvement. However, an endoscopic biopsy of the third-ventricle mass demonstrated diffuse large B-cell lymphoma. After 3 months of systemic high-dose methotrexate, all preexisting lesions disappeared, but new hemorrhagic masses were found in the right lateral ventricle and the fourth ventricle. The patient received palliative cranial radiotherapy but died 6 months after the initial diagnosis. Accurate CNS tissue diagnosis and appropriate treatment are critical.