Bone marrow features of T-cell large granular lymphocyte leukemia

Hematoxylin and eosin staining of marrow biopsy reveals a slightly hypercellular marrow with subtle increase in interstitial lymphocytes, as shown by arrow (left). Immunohistochemistry analyses (right) highlight the presence of intrasinusoidal cytotoxic T-cell infiltrates, staining positive for CD8 (arrow) and granzyme B (inset). Micrographs were viewed with a Leica Leitz DMRB microscope using a 100x/1.30 oil immersion objective. Images were captured with a Sony Exwave HAD camera and manipulated using Tribyn Version 1.3 software.