title: A clinicopathological study of primary central nervous system lymphomas & their association with Epstein-Barr virus.
abstract: OBJECTIVE
  Primary central nervous system lymphomas (PCNSLs) are relatively uncommon, accounting for 2-3 per cent of primary brain tumours. Majority of these are diffuse large B cell lymphomas (DLBCL) occurring both in immunocompromised and immunocompetent patients. We undertook this study to classify PCNSL into germinal centre (GC) and non-germinal centre (NGC) type based on Hans classification and to find the role of Epstein-Barr virus (EBV) in pathogenesis both by conventional immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH).
  
  
  METHODS
  The consecutive cases of PCNSL during a 10 years period were analysed by IHC for CD45, CD20, CD3, B-cell lymphoma 2 and 6 (Bcl-2 and Bcl-6), B-cell specific octamer binding protein-1 (BOB-1), multiple myeloma oncogene-1 (MUM-1), EBV latent-membrane protein 1 (LMP-1), cyclin-D1, CD10, CD5 and CD23, as well as by CISH for EBV.
  
  
  RESULTS
  During a period of 10 years, 65 PCNSL were diagnosed which comprised 0.69 per cent (65/9476) of all intracranial tumours. The mean age of presentation was 49 yr with sex ratio (M:F) of 1.4:1. Most common location was supratentorial region with predominant involvement of frontal lobe. Single lesions were seen in 38 (58.4%) and multifocal lesions in 27 (41.5%) patients. None of the patients were immunocompromised. All cases were B cell immunophenotype and were DLBCL except one case of follicular lymphoma. According to Hans classification, majority of them were NGC (n=51, 79.6%) and 13 (20.3%) were GC type. Bcl-2 expression was noted in 34 (52.3%) tumours. EBV was positive in three (4.6%) cases; two were detected both by IHC and CISH and one case by CISH only.
  
  
  CONCLUSIONS
  In Indian population, PCNSL occurs mainly in immunocompetent patients, and a decade earlier than in western population. Immunophenotyping revealed that all cases were DLBCL with predominance of NGC type. No prognostic difference was seen between GC and NGC DLBCL. Association of EBV was rare and this virus was possibly not involved in the pathogenesis of PCNSL in immunocompetent individuals. CISH was an easy, economical and less cumbersome method for detection of EBV in PCNSL.
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Mehar Chand
authors.initials: MC
authors.lastname: Sharma
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Rakesh Kumar
authors.initials: RK
authors.lastname: Gupta
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Seema
authors.initials: S
authors.lastname: Kaushal
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Vaishali
authors.initials: V
authors.lastname: Suri
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Chitra
authors.initials: C
authors.lastname: Sarkar
authors.affiliation: Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Manmohan
authors.initials: M
authors.lastname: Singh
authors.affiliation: Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: S S
authors.initials: SS
authors.lastname: Kale
authors.affiliation: Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Ranjit K
authors.initials: RK
authors.lastname: Sahoo
authors.affiliation: Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Lalit
authors.initials: L
authors.lastname: Kumar
authors.affiliation: Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Vinod
authors.initials: V
authors.lastname: Raina
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016543:Central Nervous System Neoplasms / Q000145:classification / Q000235:genetics / Q000473:pathology* / Q000821:virology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D016130:Immunophenotyping / Q000379:methods; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics / Q000473:pathology / Q000821:virology; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics / Q000473:pathology / Q000821:virology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D014763:Viral Matrix Proteins / Q000096:biosynthesis / Q000302:isolation & purification
chemical_list: C037662:EBV-associated membrane antigen, Epstein-Barr virus; D009363:Neoplasm Proteins; D014763:Viral Matrix Proteins