Asymptomatic T-cell large granular lymphocyte leukemia with an unusual immunophenotype.

T-cell large granular lymphocyte (T-LGL) leukemia represents a clonal proliferation of cytotoxic T-cells which etiology has not been entirely elucidated. However, CD4(+), CD4(-), CD8(-), CD4(+), CD8(+) cases have been described. The disease is usually characterized by cytopenias and a modest lymphocytosis. The majority of patients with T-LGL leukemia remains asymptomatic for a long period and will require treatment later during the course of their disease. Hereby we describe a case of T-LGL leukemia diagnosed by flow cytometry, which presented indolent course and required no treatment so far.