Central Nervous System Lymphoma

OBJECTIVE: This article reviews the clinical presentation, diagnostic workup, staging, and treatment of primary central nervous system (CNS) lymphoma and common manifestations of secondary CNS lymphoma. LATEST DEVELOPMENTS: Lymphoma can arise in the CNS de novo (primary CNS lymphoma) or as the result of systemic disease (secondary CNS lymphoma). Symptoms may include focal neurologic deficits related to the disease site, cognitive decline, and symptoms of increased intracranial pressure. Standard treatment may differ based on lymphoma subtype and location. A majority of CNS lymphoma is diffuse large B-cell subtype and exhibits aggressive behavior. First-line treatment is generally methotrexate-based polychemotherapy. Response rates to treatment are high, approximately 80% to 90% for primary CNS lymphoma, but relapse is common. Consolidation approaches including myeloablative chemotherapy followed by autologous stem cell rescue, nonmyeloablative chemotherapy, radiation, and medical maintenance regimens reduce rates of relapse. The recent development of targeted agents such as Bruton tyrosine kinase inhibitors and immunomodulatory strategies have shown promise in the treatment of CNS lymphoma. Immunotherapy in the form of checkpoint inhibitors and chimeric antigen receptor T cells is being studied. More indolent forms of lymphoma may be treated with radiation or targeted therapy. ESSENTIAL POINTS: CNS lymphoma is an uncommon but clinically meaningful manifestation of extranodal lymphoma. The diagnosis requires a high level of suspicion for rapid initiation of potentially curative treatment.