Phenotype and TCR-gamma gene rearrangements in a Malaysian cohort of T-cell leukaemia/lymphoma cases.
T cells undergo a series of complex phenotypic changes before achieving maturation. Discrete stages of T-cell differentiation are simplified to four stages (pro-, pre-, cortical and mature-T cell) and used in the classification of T-cell leukaemia. HLA-DR has been reported to be expressed in immature T-cell acute lymphoblastic leukemia (ALL) and also confer a poorer treatment outcome. Simultaneously, the genotype goes through distinct pattern changes due to rearrangement of T-cell receptor (TCR) genes. TCR gene rearrangement is important in the diagnosis of clonality and used as markers to detect minimal residual disease in lymphoproliferative disorders. We identified a subset within Pro-T and Pre-T cell cases distinguished by the expression of HLA-DR. These subgroups appeared to be more immature as rearrangement of the TCR-gamma gene was either at germline or involved only the first constant region (C1) unlike a more rearranged pattern in the HLA-DR-subgroups. We also observed a higher incidence of mediastinal mass (67%) in the HLA-DR-subgroup in the Pre-T stage. These characteristics may be useful as markers to further refine staging of T-cell ALL and determine prognosis.
Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia. maha@medic.upm.edu.my
Abdullah
A
Maha
Gin Gin
GG
Gan
Chong-Lek
CL
Koh
D000293:Adolescent; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D015415:Biomarkers; D002454:Cell Differentiation; D002648:Child; D002675:Child, Preschool; D005260:Female; D015329:Gene Rearrangement, T-Lymphocyte; D019672:Genes, T-Cell Receptor / Q000235:genetics; D006684:HLA-DR Antigens; D006801:Humans; D015458:Leukemia, T-Cell / Q000145:classification / Q000235:genetics / Q000473:pathology; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000145:classification / Q000235:genetics / Q000473:pathology*; D008296:Malaysia; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011379:Prognosis; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics*; D055815:Young Adult
D015703:Antigens, CD; D015415:Biomarkers; D006684:HLA-DR Antigens; D016692:Receptors, Antigen, T-Cell, gamma-delta