title: Clinical relevance of flow cytometric immunophenotyping of the cerebrospinal fluid in patients with diffuse large B-cell lymphoma.
abstract: BACKGROUND
  Central nervous system (CNS) relapse is an uncommon but dramatic complication of diffuse large B-cell lymphoma (DLBCL). Several studies have demonstrated the superiority of cerebrospinal fluid (CSF) flow cytometry (FCM), as compared with conventional cytology (CC), in detecting occult leptomeningeal disease. The clinical relevance of a positive FCM still has to be clarified.
  
  
  METHODS
  We analyzed CSF from 114 DLBCL patients at diagnosis (n = 95) or at relapse (n = 19) by FCM and CC. Most patients received meningeal prophylaxis. FCM results did not influence treatment strategies.
  
  
  RESULTS
  Fourteen samples were FCM+, versus one CC+ (also FCM+). Within all patients without neurological symptoms (n = 101), four (4%) relapsed in the CNS, with a median time to relapse of 5.2 months. Only one-fourth (25%) was FCM+ before relapse. More than one extranodal disease site and elevated lactate dehydrogenase levels were associated with an increased risk of CNS relapse.
  
  
  CONCLUSIONS
  FCM gives far more positive results than CC. However, a positive FCM result did not translate into a significant increase in CNS relapse rate in this histologically uniform population receiving CNS prophylaxis.
authors.affiliation: Lymphoid Malignancies Unit.
authors.forename: R
authors.initials: R
authors.lastname: Alvarez
authors.affiliation: Lymphoid Malignancies Unit. Electronic address: jehan.dupuis@hmn.aphp.fr.
authors.forename: J
authors.initials: J
authors.lastname: Dupuis
authors.affiliation: Immunology Laboratory, Centre Hospitalo-Universitaire Henri Mondor, Assistance Publique - Hôpitaux de Paris, Paris; Université Paris-Est Créteil, Créteil.
authors.forename: A
authors.initials: A
authors.lastname: Plonquet
authors.affiliation: Cytology Laboratory.
authors.forename: C
authors.initials: C
authors.lastname: Christov
authors.affiliation: Université Paris-Est Créteil, Créteil; Department of Pathology.
authors.forename: C
authors.initials: C
authors.lastname: Copie-Bergman
authors.affiliation: Department of Biostatistics.
authors.forename: F
authors.initials: F
authors.lastname: Hemery
authors.affiliation: Lymphoid Malignancies Unit.
authors.forename: I
authors.initials: I
authors.lastname: Gaillard
authors.affiliation: Lymphoid Malignancies Unit.
authors.forename: T
authors.initials: T
authors.lastname: El Gnaoui
authors.affiliation: Lymphoid Malignancies Unit.
authors.forename: F
authors.initials: F
authors.lastname: Kuhnowski
authors.affiliation: Lymphoid Malignancies Unit.
authors.forename: M
authors.initials: M
authors.lastname: Bedoui
authors.affiliation: Lymphoid Malignancies Unit.
authors.forename: K
authors.initials: K
authors.lastname: Belhadj
authors.affiliation: Department of Neuroradiology, Centre Hospitalo-Universitaire Henri Mondor, Assistance Publique - Hôpitaux de Paris, Paris, France.
authors.forename: P
authors.initials: P
authors.lastname: Brugières
authors.affiliation: Lymphoid Malignancies Unit; Université Paris-Est Créteil, Créteil.
authors.forename: C
authors.initials: C
authors.lastname: Haioun
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016543:Central Nervous System Neoplasms / Q000134:cerebrospinal fluid / Q000175:diagnosis* / Q000556:secondary; D003581:Cytodiagnosis / Q000379:methods; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D016130:Immunophenotyping / Q000379:methods*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000134:cerebrospinal fluid* / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012008:Recurrence; D055815:Young Adult