Tumor lysis syndrome occurring after the administration of rituximab in lymphoproliferative disorders: high-grade non-Hodgkin's lymphoma and chronic lymphocytic leukemia.

Rituximab, an anti-CD20 antibody, has been recently approved for the treatment of low-grade or follicular non-Hodgkin's lymphoma (NHL). Because of its relatively benign side effect profile, it has been considered a nontoxic alternative to chemotherapy. Recently, however, tumor lysis syndrome (TLS) resulting from rituximab has been reported in a patient with chronic lymphocytic leukemia (CLL). We herein present two cases of rituximab-induced TLS. The first case occurred in a patient with high-grade NHL, while the second case occurred in a patient with CLL. We also present a summary of the literature regarding TLS induced by immunotherapies. Copyright 1999 Wiley-Liss, Inc.