Thelansis

  T-cell large granular lymphocyte leukemia (T-LGL) is a heterogeneous lymphoproliferative disorder of CD3-positive T cells. The median age of T-LGL diagnosis is 60, with an equal male-to-female ratio and an indolent clinical course. A positive rheumatoid factor is found in 60%, polyclonal hypergammaglobulinemia in 10–40%, and a positive Coombs test in 15% of patients. The diagnostic criteria for LGL include a persistent increase in circulating LGLs, confirmatory immunophenotype, and, ideally clonal T cell receptor (TCR) rearrangements. T-LGL leukemia has a mature T cell immunophenotype, with 80% of patients expressing CD3, CD8, and TCRab, but not CD4, and discrepant weak CD5 or CD7 expression. Rare variants may be CD4þ and CD8– or co-expression of CD4 and CD8. Large granular lymphocytes form part of the cellular immune response and produce tumor necrosis factor a and interferon g, leading to cell lysis of damaged cells, such as virally infected cells. Secondary to chronic activa...

 T-cell large granular lymphocyte leukemia (T-LGL) is a heterogeneous lymphoproliferative disorder of CD3-positive T cells. The median age of T-LGL diagnosis is 60, with an equal male-to-female ratio and an indolent clinical course. A positive rheumatoid factor is found in 60%, polyclonal hypergammaglobulinemia in 10–40%, and a positive Coombs test in 15% of patients. The diagnostic criteria for LGL include a persistent increase in circulating LGLs, confirmatory immunophenotype, and, ideally clonal T cell receptor (TCR) rearrangements. T-LGL leukemia has a mature T cell immunophenotype, with 80% of patients expressing CD3, CD8, and TCRab, but not CD4, and discrepant weak CD5 or CD7 expression. Rare variants may be CD4þ and CD8– or co-expression of CD4 and CD8. Large granular lymphocytes form part of the cellular immune response and produce tumor necrosis factor a and interferon g, leading to cell lysis of damaged cells, such as virally infected cells. Secondary to chronic activatio...