CD4 and T-cell large granular lymphocyte leukemia: In addition to the most common CD8+ T-LGL leukemia, less frequent LGL proliferations with CD4+/CD8-/+dim phenotype (CD4+ T-LGL leukemia) exist, which are characterized by a typical Vβ13.1 expression, frequent association with secondary neoplasia and a pathogenetic relationship with CMV infection [6].