Incidence of tumor lysis syndrome in children with advanced stage Burkitt's lymphoma/leukemia before and after introduction of prophylactic use of urate oxidase

To evaluate the clinical benefit of the prophylactic use of urate oxidase in children with non-Hodgkin's lymphoma. (NHL), we analyzed the incidence and complications of tumor lysis syndrome (TLS) in children with B-cell acute lymphoblastic leukemia (B-ALL) or stage III/IV Burkitt's lymphoma and a lactate dehydrogenase (LDH) level greater than or equal to500 U/l before and after the introduction of a protocol amendment to use urate oxidase for the prophylaxes of TLS. Data from 1791 children with NHL enrolled in the two subsequent multicenter studies NHLBFM 90 and 95 were evaluated. The presence of the side effects TLS, anuria, sepsis, and other complications during the first 2 weeks after admission were registered. Until March 1996, no urate oxidase was used (period 1). From November 1997 all children with B-ALL or stage III and IV B-NHL and LDH greater than or equal to500 U/l should receive urate oxidase prophylactically (period 3). In between (period 2), urate oxidase was given in a minority of hospitals therapeutically. Initial chemotherapy was identical. Altogether, 78 children (4.4%) developed a TLS. Patients with B-ALL had the highest risk to develop a TLS (26.4%) followed by B-ALL/Burkitt's lymphoma and a LDH greater than or equal to500 U/l (14.9%). In period 1, 16.1% and 9.2% of the latter children developed a TLS or anuria, respectively, compared to 12.3% and 6.2% in period 3 (p=NS). The incidence of sepsis remained unchanged (5.0% vs 4.6%). In children with B-ALL the differences in the incidence of TLS and anuria between period 3 and period 1 were more pronounced, reaching significance for anuria (15.4% vs 3.8%, p=0.03). Our results suggest that patients with the highest risk to develop a TLS might benefit from the prophylactic use of urate oxidase.