CD56-Negative Aggressive NK Cell Leukemia Relapsing as Multiple Cranial Nerve Palsies: Case Report and Literature Review

Figure 3

Flow cytometry studies in the bone marrow aspirate, using the EuroFlow lymphoid screening tube (LST) and antibody panel for NK cell chronic lymphoproliferative diseases (NK-CLPD), consisting of 8-color combinations of monoclonal antibodies (7), and a FACSCanto II flow cytometer (Becton Dickinson). Data analysis was performed using the Infinicyt software (Cytognos, Spain). Dot-plots illustrate the phenotypic features of the neoplastic NK cells. Blue dots correspond to the neoplastic NK cells whereas pink dots and yellow dots are the normal residual T cells and B cells present in the bone marrow sample. Other cells are represented as gray dots. The abnormal NK cells were positive for surface CD45 (high), CD2, CD26, CD38, CD94 (high), and HLA-DR and cytoplasmic granzyme B and perforin; and they were negative for surface CD3, CD4, CD5, CD7, CD8, CD11c, CD16, CD19, CD20, CD25, CD56, Ig kappa, and lambda chains.