Rituximab in pediatric B-cell Non-Hodgkin Lymphoma: Clinical outcomes and prognostic implications

Objective: B-cell Non-Hodgkin Lymphoma (B-NHL) is an aggressive malignancy in children requiring prompt multidisciplinary management. This retrospective cohort study aims to evaluate the clinical characteristics, treatment outcomes, and impact of rituximab (RTX) in pediatric B-NHL patients. Methods: We retrospectively analyzed 62 pediatric B-NHL patients treated at tertiary centers. Patient demographics, clinical presentation, histopathological subtypes, disease stage, treatment regimens, and survival outcomes were assessed. Event-free survival (EFS) and overall survival (OS) rates were analyzed based on lactate dehydrogenase (LDH) levels and RTX administration. Results: The mean age at diagnosis was 8.73 +/- 4.3 years, with a male predominance (79%). The most common histological subtype was Burkitt lymphoma (BL) (53.2%), followed by diffuse large B-cell lymphoma (DLBCL) (33.8%). Advanced-stage disease (III-IV) was observed in 74.1% of cases. RTX was administered in 72.5% of patients, with a mean of 5.1 +/- 2.7 doses. Febrile neutropenia (FEN) was noted in 74.1%, with intensive care unit (ICU) admission required for seven patients. Mortality was observed in 12 (19.3%) patients, including all patients with primary immunodeficiency (PID). The 5-year EFS for the entire cohort was 67.2%, and OS was 81.3%. Patients with LDH <400 U/L had superior 5-year EFS (88.9%) and OS (96.3%) compared to those with LDH >400 U/L (EFS: 49.6%, OS: 70.7%; p=0.004 and p=0.015, respectively). In RTX-treated patients without PID, EFS was 76.5% versus 73.2% in those without RTX, but the difference was not statistically significant (p=0.53). Conclusions: Although not statistically significant, EFS was found to be higher in the RTX-treated group, suggesting that adding RTX to standard chemotherapy regimens may improve survival, particularly for high-risk patients, though its benefit in low-risk cases remains uncertain. Despite improved survival, patients with PID had poor outcomes, likely due to increased infections and disseminated disease. Risk-adapted, targeted treatment strategies are essential for optimizing outcomes in pediatric B-NHL. Further large-scale, randomized controlled trials are needed to confirm the efficacy of RTX in different risk groups and to optimize treatment regimens for pediatric B-NHL.