title: Characterization of T-cell non-Hodgkin's lymphoma and its association with Epstein-Barr virus in Pakistani patients.
abstract: This study analyzes the prevalence of T-cell non-Hodgkin's lymphoma (T-NHL) in a major referral center of Pakistan and its association with Epstein-Barr virus (EBV). Ninety-two cases of T-NHL were characterized on the basis of morphology, immunohistochemistry and genetic features. The prevalence of T-NHL was 22.2% of the total NHLs diagnosed during the eight years period (1992-1999). Polymerase chain reaction (PCR) technique was used to assess T-cell clonality in paraffin-embedded tissues of known T-NHL. Amplifiable DNA was isolated from all the cases, which were further studied for T-cell receptor (TcR)-beta, gamma, delta, and IgH chain gene rearrangements. Out of 92 cases 51 cases showed clonal product and 33 demonstrated polyclonal smear for beta, gamma, or delta chain genes, respectively, whereas 8 cases exhibited IgH chain gene rearrangement for FR2 region. This study demonstrated frequent presence of EBV in T-NHL (55.4%) by PCR, which were further tested for the localization of the virus by in situ hybridization (ISH). The extent of polymorphism in EBV genome was studied by single stranded conformation polymorphism (SSCP) technique for Bam HI E, K, N and Z regions. Hypervariability in Bam HI K, and N regions was noticeably higher compared to E or Z regions. In conclusion, our study demonstrated that the prevalence of T-NHL in Pakistan is slightly higher to that reported for Western communities. In addition, the frequency of EBV genome in T-NHL is intermediate as compared to other studies. No association was established between EBV variants differentiated on the basis of sequence heterogeneity in Bam HI K, N, E and Z regions with the manifestation of different subsets of T-NHL.
authors.affiliation: Department of Pathology, Faculty of Health Sciences, Medical College, Aga Khan University, Department of Microbiology, University of Karachi, Karachi, Pakistan.
authors.forename: Samina
authors.initials: S
authors.lastname: Noorali
authors.forename: Shahid
authors.initials: S
authors.lastname: Pervez
authors.forename: Tariq
authors.initials: T
authors.lastname: Moatter
authors.forename: Irshad Nabi
authors.initials: IN
authors.lastname: Soomro
authors.forename: Shahana Urooj
authors.initials: SU
authors.lastname: Kazmi
authors.forename: Muhammad Israr
authors.initials: MI
authors.lastname: Nasir
authors.forename: John Lewis
authors.initials: JL
authors.lastname: Smith
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002999:Clone Cells / Q000473:pathology; D004279:DNA, Viral / Q000235:genetics; D020031:Epstein-Barr Virus Infections / Q000150:complications* / Q000453:epidemiology; D005260:Female; D015321:Gene Rearrangement; D019672:Genes, T-Cell Receptor; D004854:Herpesvirus 4, Human / Q000235:genetics*; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D016399:Lymphoma, T-Cell / Q000453:epidemiology / Q000235:genetics* / Q000821:virology*; D008297:Male; D008875:Middle Aged; D010154:Pakistan / Q000453:epidemiology; D015995:Prevalence; D012189:Retrospective Studies
chemical_list: D004279:DNA, Viral; D007143:Immunoglobulin Heavy Chains