INTRODUCTION: In diffuse large B-cell lymphoma (DLBCL), approximately 5-10% of patients develop secondary central nervous system (CNS) involvement. CNS disease is associated with very poor outcomes. Therefore, it is important to identify patients at risk, via the CNS International Prognostic Index (IPI), in order to initiate appropriate interventions. Additional independent risk factors for CNS involvement include HIV-related lymphoma and high-grade B-cell lymphomas. The purpose of this study was to assess for appropriate CNS evaluation and prophylaxis in DLBCL patients within the Veterans Health Administration (VHA).
METHODS: We performed a retrospective chart review of 1,605 randomly selected patients seen in the VHA nationwide who were diagnosed with lymphoma between January 1, 2011 and December 31, 2017. We included patients diagnosed with DLBCL and excluded patients diagnosed or treated outside the VHA. We evaluated CNS IPI score, HIV status, pathology reports to identify high-grade lymphomas, performance of lumbar puncture (LP), and administration of CNS prophylaxis.
RESULTS: A total of 725 patients met our inclusion criteria. Patients were predominantly male (96.8%), white (74.5%), had a median age of 67, and presented with advanced disease (stage III 26.5%, stage IV 40.3%). From the included population, 190 (26.2%) had a highrisk CNS IPI score. Of those with high-risk CNS IPI scores, 64 (33.7%) underwent LP and 46 (24.2%) were treated with CNS prophylaxis. 23 (3.2%) were HIV positive; of those, 14 (60.8%) underwent LP and 4 (17.4%) were treated with CNS prophylaxis. FISH results were available in only 242 (33.4%) of patients and of these, 25 (10.3%) met criteria for high-grade lymphoma. Of those with high-grade lymphoma, 9 (36%) underwent LP and 7 (28%) were treated with CNS prophylaxis.
CONCLUSIONS: The National Comprehensive Cancer Network guidelines recommend that patients at high risk for CNS involvement undergo LP and treatment with CNS prophylaxis. This study found that within the VHA, patients with DLBCL at high risk for CNS involvement are not being evaluated with LPs or treated with CNS prophylaxis as often as indicated, based on CNS IPI, HIV status, and high-grade pathology. We demonstrate a need for improvement in the evaluation and treatment of these patients in order to improve outcomes.