Direct CNS administration of rituximab and epratuzumab in a pediatric patient with relapsed refractory CNS B-cell acute lymphoblastic leukemia.

Relapsed central nervous system (CNS) leukemia presents a therapeutic challenge to pediatric oncologists. Systemic monoclonal antibody therapy has shown recent promise in patients with relapsed acute lymphoblastic leukemia, however its effect on CNS disease in this population is not well established. We describe a case of multiply relapsed and refractory CNS leukemia in an adolescent patient who responded to the intra-CNS delivery of rituximab (anti-CD20) and epratuzumab (anti-CD22) therapy, demonstrating the practical use and potential efficacy of a novel route of monoclonal antibody administration in difficult-to-treat CNS leukemia.