High incidence of activating STAT5B mutations in CD4-positive T-cell large granular lymphocyte leukemia

To the editor: Large granular lymphocyte (LGL) leukemia is a group of chronic lymphoproliferative disorders of cytotoxic T or natural killer (NK) cells frequently complicated with cytopenia and autoimmune phenomena.[1][1],[2][2] In the current World Health Organization (WHO) classification, T-LGL