Central Nervous System Lymphoma

Central nervous system lymphoma (CNSL) is a rare and aggressive malignancy that primarily affects the brain, spinal cord, and meninges. This article provides a comprehensive overview of the current understanding of CNSL encompassing its epidemiology, pathophysiology, clinical presentation, diagnosis, treatment modalities, and prognosis. Although the main focus is on primary CNS lymphoma (PCNSL), ocular lymphoma, primary leptomeningeal lymphoma, and secondary CNS lymphoma are also discussed. The pathobiology of CNSL involves the infiltration of malignant lymphocytes within the CNS parenchyma or leptomeninges. Various risk factors and immunological mechanisms contribute to its development, including immunodeficiency states, chronic inflammation, and genomic alterations. Accurate diagnosis is crucial for appropriate management, given the heterogeneous clinical presentation. The neuroimaging, systemic imaging, and other modalities for diagnosis and evaluation for extent of disease involvement will be discussed. Additionally, the importance of histopathological examination, cerebrospinal fluid (CSF) analysis, and molecular testing in confirming the diagnosis and guiding treatment decisions are highlighted. The treatment landscape for CNSL has evolved significantly. Therapeutic approaches encompass a multimodal strategy combining high-dose methotrexate-based chemotherapy, consolidation with whole-brain radiation therapy, and high-dose chemotherapy with stem cell rescue. Recent advancements in targeted therapies and immunomodulatory agents offer promising avenues for future treatment options. We review the clinical outcomes and prognostic factors influencing the survival of CNSL patients, including age, performance status, disease stage, and genetic abnormalities.