title: Prevalence and characterization of anaplastic large cell lymphoma and its association with Epstein-Barr virus in Pakistani patients.
abstract: Anaplastic large cell lymphoma (ALCL), CD30+, is a subtype of T-non-Hodgkin's lymphoma (NHL). Its most common form is a classical systemic type that involves multiple nodal and extranodal sites. In this study, morphologic, immunohistologic, and genetic studies were performed on ALCL cases in Pakistani patients. The median age of the patients in this study was 45 years (age range: 5-70 years), with a male to female ratio of 3.4:1. Thirty-seven (37) patients were diagnosed to have Ki-1 (CD30+) ALCL, which constituted 2% of all NHLs and 12.6% of all T-NHLs, over a period of 11 years (January 01, 1992-December 31, 2002). The tumors were of either T- or null-cell type with constant (100%) expression of CD30 (Ki-1). The majority of the cases (89.2%) expressed EMA, whereas 40.5% of the cases expressed either CD45 (LCA), CD45RO (UCHL1), or ALK. The mean age of ALCL patients with null-cell phenotype was 33.8 years as compared to those with T-cell phenotype having a mean age of 36.3 years. Out of the 37 cases diagnosed as ALCL, amplifiable DNA was isolated from 28 cases, which were further assessed for T-cell clonality for T-cell receptor (TCR)-beta, gamma, and immunoglobulin heavy chain (IgH) for the FR2 and FR3 regions. The polymerase chain reaction (PCR) technique demonstrated clonal rearrangement of the TCR beta, gamma, and IgH regions in 15 (53.6%), 11 (39.3%), and 2 (7.1%) ALCL cases, respectively, out of 28 cases. Association of Epstein-Barr virus (EBV) was noted in seven out of 28 cases (25%) of ALCL by PCR, whereas ISH for EBV-encoded nuclear RNA-1 (EBER-1) detected the presence of EBV in two (16.7%) out of 12 cases, where one was T-cell ALCL and the other null-cell ALCL. Immunostaining for LMP-1 could not be performed, because tissue material was not available. In conclusion, our study demonstrated that the prevalence of ALCL in Pakistan is comparable to that reported for some of the Asian communities and by the International Lymphoma Study Group and that EBV could be partly responsible for the pathogenesis of ALCL.
authors.affiliation: Department of Pathology and Microbiology, The Aga Khan University, Medical Centre, Stadium Road, P.O. Box 3500, Karachi 74800, Pakistan.
authors.forename: Samina
authors.initials: S
authors.lastname: Noorali
authors.forename: Shahid
authors.initials: S
authors.lastname: Pervez
authors.forename: Nausheen
authors.initials: N
authors.lastname: Yaqoob
authors.forename: Tariq
authors.initials: T
authors.lastname: Moatter
authors.forename: Muhammad Israr
authors.initials: MI
authors.lastname: Nasir
authors.forename: Sarwat
authors.initials: S
authors.lastname: Haroon
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hodges
authors.forename: John Lewis
authors.initials: JL
authors.lastname: Smith
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000077548:Anaplastic Lymphoma Kinase; D018951:Antigens, CD20 / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D020031:Epstein-Barr Virus Infections / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D005260:Female; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D004854:Herpesvirus 4, Human; D006801:Humans; D007143:Immunoglobulin Heavy Chains; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D017730:Ki-1 Antigen / Q000378:metabolism; D017493:Leukocyte Common Antigens / Q000378:metabolism; D016403:Lymphoma, Large B-Cell, Diffuse / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D008297:Male; D008875:Middle Aged; D010154:Pakistan; D016133:Polymerase Chain Reaction; D015995:Prevalence; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D012367:RNA, Viral / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases; D014412:Tumor Virus Infections / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*
chemical_list: D018951:Antigens, CD20; C099537:Epstein-Barr virus encoded RNA 1; D007143:Immunoglobulin Heavy Chains; D017730:Ki-1 Antigen; D012367:RNA, Viral; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; D017493:Leukocyte Common Antigens