Lymphoproliferative disorder of granular lymphocytes. A heterogeneous disease.
Lymphoproliferative disorders of granular lymphocytes (LDGLs) represent a family of diseases that are morphologically similar but diverse with regard to immunophenotype, function, and clonality. In this article, we report three informative cases and propose a modification of the current classification of LDGLs. Our first case is an example of natural killer cell LDGLs (CD2+, CD3-, CD16+, CD57+/-). Based on a review of the literature, we suggest that natural killer cell LDGLs can be divided into two subgroups (types 1 and 2) according to the expression of CD57. Reduced expression of CD57 may distinguish between patients with a poorer prognosis. The remaining two cases illustrate examples of T-cell LDGLs (CD2+, CD3+, CD8+, CD57+) that differ mainly in their expression of CD16. The CD16+ T-cell LDGLs (type 1) usually show a clonal rearrangement of the T-cell receptor-beta chain gene, whereas CD16- T-cell LDGLs (type 2) may show a germline configuration, suggesting a reactive rather than a neoplastic process. Pathologists should differentiate LDGLs from other chronic lymphoproliferative diseases, since most cases evolve slowly and aggressive cytoreductive therapy is usually unwarranted.
McDaniel
H L
HL
Department of Pathology, University of Vermont College of Medicine, Burlington.
MacPherson
B R
BR
Tindle
B H
BH
Lunde
J H
JH
D000328:Adult; D015703:Antigens, CD / Q000032:analysis*; D000943:Antigens, Differentiation / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D017252:CD3 Complex; D018959:CD57 Antigens; D004247:DNA / Q000378:metabolism; D006801:Humans; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000276:immunology; D008232:Lymphoproliferative Disorders / Q000145:classification / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011948:Receptors, Antigen, T-Cell / Q000032:analysis / Q000276:immunology; D011961:Receptors, Fc / Q000032:analysis; D017452:Receptors, IgG; D013601:T-Lymphocytes / Q000276:immunology
D015703:Antigens, CD; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D018959:CD57 Antigens; D011948:Receptors, Antigen, T-Cell; D011961:Receptors, Fc; D017452:Receptors, IgG; D004247:DNA