Central Nervous System Infiltration in Chronic Lymphocytic Leukemia: A Study on Behalf of the Registro Brasileiro De Leucemia Linfocitica Cronica

ABSTRACT

Introduction: Central nervous system (CNS) infiltration in chronic lymphocytic leukemia (CLL) is a rare presentation of CLL that can potentially have disastrous complications. Reported prognosis is poor. The objective of this study is to report a series of cases of CLL with CNS infiltration. Method(s) This is a case-series of a Brazilian CLL registry (Registro Brasileiro de Leucemia Linfocitica Cronica). We included patients with CLL and CNS infiltration. This is a descriptive study. Result(s) A total of 10 (0.28%) in 3610 patients were identified with confirmed (80%) or suspected (20%) CNS infiltration. Median age at CLL diagnosis was 57.5 y/o (range 50 - 76). Three (30%) patients were diagnosed with CNS infiltration concomitantly with the CLL diagnosis, while others (70%) were diagnosed at a median of 41 months of CLL diagnosis (range 11 to 119 months). Only three (30%) patients had been previously treated for CLL. Most common symptoms of CNS infiltration were convulsion (30%), altered mental status (30%), headaches (30%), ophthalmologic (30%), and urinary incontinence (20%). Amnesia, asthenia, vomiting, hemiparesis, cervicalgia, and dizziness were also present (one patient each). Of the patients with confirmed CNS infiltration, diagnoses were performed through liquor exam (all patients) and biopsy (one patient). Of the two patients with suspected CNS infiltration, one achieved complete response and the other, partial clinical response, following instituted CLL-directed therapy with (1 patient) or without (1 patient) intrathecal chemotherapy. Of the other 8 patients, 3 achieved complete response, 2 failed treatments, 1 was not evaluated and 2 had missing information. Of all patients, 5 are alive, 3 died of sepsis, multiorgan failure following CNS methotrexate-related toxicity, and COVID, and 2 had missing information. Discussion(s) Our results show that the prognosis of CNS infiltration in CLL can be relatively good, with at least 50% of patients alive at 1 year. However, a series of 18 patients published by Strati et al has shown a poorer outcome, with half of the patients dead at 1 year. Although all patients were diagnosed by liquor exam, that same study reported a low specificity for liquor exam in CLL (42%) due to the frequent presence of leukemic cells in the cerebrospinal fluid in other conditions. Establishing CNS CLL as the cause of the symptoms can be difficult, since up to 70% of patients with CLL have CNS infiltration in autopsy studies, and our results may be superestimated. In summary, CNS infiltration in CLL is a rare event, and further studies are needed to address prognosis and management. Copyright © 2022