Pharmacotherapy of primary CNS lymphoma

Primary CNS lymphoma (PCNSL) is distinguished from other brain tumours by its striking response to chemotherapy. Surgery has little role (if any) in the treatment of PCNSL. Radiation therapy has been proven to prolong survival but its use is complicated by delayed neurological toxicity, particularly among the elderly. Progress in understanding the physiology of the blood-brain barrier (BBB) and the pharmacology of chemotherapeutic agents has substantially improved the treatment and prognosis of this disease. The single most effective agent is methotrexate (MTX). The goal of delivering an adequate dose of MTX to the brain and the cerebrospinal fluid (CSF) has been achieved by a variety of strategies, including systemic high dose, intra-arterial injection following pharmacological disruption of the BBB and intrathecal (it.) administration. MTX-based combination chemotherapy has yielded the best results to date but the prognosis of patients with PCNSL remains significantly worse than comparable patients with systemic non-Hodgkin's lymphoma (NHL). Ongoing trials continue to test novel combinations of agents, doses and improved routes of delivery with the hope of improving disease control and diminishing treatment-related neurotoxicity.