Rituximab can be useful as treatment for minimal residual disease in bcr-abl-positive acute lymphoblastic leukemia

We report the results of administering CD20 monoclonal antibody (MoAb) in a 32-year-old man with bcr-abl-positive acute lymphoblastic leukemia. Morpho logical complete remission was achieved after two lines of chemotherapy wit h persistence of blast cells (2%) in flow cytometric analysis of marrow cel ls. Since no HLA-matched donor for allogeneic bone marrow transplantation ( BMT) was found, anti-CD20 MoAb therapy was administered for in vivo marrow purging, prior to autologous peripheral blood stem cell (PBSC) harvest and transplantation. After MoAb therapy <0.1% of blast cells were observed and the molecular abnormality (bcr-abl gene rearrangement) disappeared.