ABSTRACT
BACKGROUND AND OBJECTIVES: Pediatric B-cell non-Hodgkin lymphomas (NHL) in low- and middle-income countries (LMICs) have historically had inferior outcomes due to higher treatment-related mortality (TRM) and relapses. To address this issue, we evaluated the impact of reducing chemotherapy dose intensity by 25% and adding rituximab on outcomes in pediatric B-NHL. PATIENTS AND METHODS: Patients, less than 18 years of age with group B and C disease as per the Lymphome Malin de Burkitt (LMB) risk stratification were enrolled between September 2017 and October 2022. The LMB-89 protocol, with a 25% reduction in all chemotherapy doses and the addition of rituximab, was administered. The response was assessed using positron emission tomography with computed tomography (PET/CT) after four cycles of chemotherapy (interim) and at the end of treatment. RESULTS: The study included 25 patients with a median age of 6.9 years, among whom 20 (80%) were males. Twenty patients had group B and five had group C disease. Complete metabolic response (CMR) was achieved by 22/25 (88%) patients, and three (12%) achieved partial metabolic response (PMR) in the interim PET/CT. At the end of treatment, 22/24 (92%) patients achieved CMR, one had PMR, and one had progressive disease. The median follow-up was 45 months (range: 3-71 months). The 4-year event-free survival and overall survival were 88% and 92%, respectively. There were two deaths, one due to disease progression and the other due to sepsis. CONCLUSION: Our study demonstrates a significant improvement in outcomes in pediatric B-NHL compared to previous reports from LMICs, achieved through a 25% reduction in chemotherapy dose intensity and the addition of rituximab.
ABSTRACT
Rasburicase is a recombinant urate oxidase enzyme approved for use in tumor lysis syndrome (TLS) and it acts by reducing serum uric acid levels. Using rasburicase at the recommended dose of 0.2 mg/kg/day for 5 days is expensive and it is not known whether this extended schedule is clinically beneficial compared to a single fixed dose of 1.5 mg. The aim of the present study was to evaluate the efficacy of single dose rasburicase 1.5 mg in prevention and management of TLS. Rasburicase is available as single use 1.5 mg vial. At our institution a single dose of rasburicase 1.5 mg irrespective of bodyweight has been used in adults and in children a dose of 0.15 mg/kg (maximum 1.5 mg) has been used since 2012 for prevention and management of TLS and subsequent doses are given based on biochemical response and clinical condition. We retrospectively analysed the case records of patients who had received rasburicase from January 2012 to January 2017. The study included 186 patients with hematological malignancies who received rasburicase. Children accounted for 56.4% (n = 105) patients and males comprised 73% (n = 135). Rasburicase was used prophylactically in 59 (31.7%) patients, for laboratory TLS in 76 patients (40.8%) and for clinical TLS in 51 (27.4%) patients. Single fixed dose rasburicase prevented laboratory/clinical TLS in 87% of the prophylactic group and prevented clinical TLS in 72% of the laboratory TLS group. None of the patients in prophylactic and laboratory TLS group developed clinical TLS. However, majority of the patients with clinical TLS required more than one dose rasburicase. Single dose of 1.5 mg (1 vial) rasburicase is efficient in preventing and managing laboratory TLS and is economically viable in resource constrained settings.
