2 of 7 Primary CNS Lymphoma CSF Analysis

Primary central nervous system lymphoma (PCNSL) is a rare subtype of non-Hodgkin’s lymphoma in which disease is restricted to the craniospinal axis [1]. Ocular involvement can occur in 10-20% of cases and leptomeningeal disease is documented in 20-30%. PCNSL represents 2% of all lymphoma diagnoses (and 3% of all brain tumour presentations) and the incidence is reported in the range of 4 cases/million person-years. The only known risk factor for PCNSL development is congenital or acquired immunodeficiency. In the recent era of highly active antiretroviral therapy use, a dramatic reduction in incidence of immunodeficiencyassociated PCNSL has occurred, correlating with a decline in the proportion of HIV-infected individuals with CD4+ cell counts less than 50/mm3 [2]. The majority of this document will focus on the management of PCNSL in immunocompetent individuals with a brief discussion of HIV-associated PCNSL. A practice guideline on the management of PCNSL has been published by the British Committee for Standards in Haematology (BCSH) www.bcshguidelines.com [3]. The Odette Cancer Centre Hematology Site Group endorses this document.