Impaired renal function and tumor lysis syndrome in pediatric patients with non-Hodgkin's Lymphoma and B-ALL - Observations from the BFM-trials

Objective Tumor lysis syndrome and renal failure remain important complications early in the course of therapy for pediatric Non-Hodgkin's lymphoma (NHL), frequently leading to therapeutic alterations. In the presented series, children with NHL and tumor lysis syndrome are retrospectively analysed regarding clinical features of acute renal failure and its implications on therapy. Patients and methods From 4/1990 to 10/1997, 1192 patients diagnosed of any form of NHL have been registered in the NHL-BFM trials. 63 of these patients were reported to have suffered from impaired renal function and/or tumor lysis syndrome before or during initial treatment. Clinical data of these patients were analysed regarding diagnosis, stage, tumor mass, therapy and complications. Results 62 of 63 patients with impaired renal function and/or tumor lysis syndrome were diagnosed of Burkitt's lymphoma or B-ALL; 58 (92%) of these patients had advanced stages of disease and high LDH-levels (>500 U/l). 43 of 63 patients had already signs of impaired renal function at admission. Hyperuricemia was the commonest cause of impaired renal function. Renal infiltration or enlargement was observed in 27 of 63 patients. 6 patients were diagnosed of urinary tract obstruction. 25 patients required hemodialysis. Despite improved renal function before administration of MTX, 21 of 63 patients suffered from protracted MTX-elimination during the first course of therapy. 7 of 63 patients (11%) with tumor lysis syndrome died of sepsis after the first course of therapy, another two patients died within 48 hours of therapy due to electrolyte imbalances. Conclusions In pediatric NHL-patients, Burkitt's lymphoma and B-ALL appear to be the commonest cause of metabolic complications early in chemotherapy. Patients with advanced stages and large tumor mass are at high risk for renal failure. Impaired renal function predisposes patients to further complications and toxic death. Prophylactic use of urate-oxidase in all patients with advanced stage NHL might limit the incidence of tumor lysis syndrome. Prospective studies on renal function prior to and during therapy are required in order to develop a clinical profile reliably detecting patients at risk for developing renal failure and subsequent complications.