Pediatric B-cell Non-Hodgkin Lymphoma: The Impact of Therapy Response and Relapse on Outcome. A Single-center Analysis

Background/Aim: Pediatric patients with primary refractory or relapsed B-cell non-Hodgkin lymphoma (B-NHL) have highly unfavorable prognosis. In this study, we retrospectively analyzed outcomes in pediatric B-NHL patients treated in a single center in Poland from 1995 to 2022, with emphasis on therapy results in patients with progression or relapse. Patients and Methods: The primary objectives were a 5-year probability of overall survival (pOS) and a 5-year probability of event-free survival (pEFS). The secondary objectives involved the assessment of prognostic factors. Results: A total of 76 children were eligible for the analysis. The 5-year pOS was 76.7%, and the 5-year pEFS was 72.9%. At diagnosis, elevated lactate dehydrogenase activity, the presence of B symptoms, bone marrow, skeletal or mediastinal involvement, and stage IV disease were associated with inferior outcomes. Nine children experienced progression and four relapse. The 5-year pOS for patients with progression was 38.1%. Two patients treated with hematopoietic stem cell transplantation (HSCT) as part of salvage therapy survived. However, only one out of seven patients who were treated without HSCT survived. The 5-year pOS was 0.0% in patients with relapsed disease. Conclusion: The most significant factor related to outcomes in pediatric B-NHL is therapy response, with a high mortality rate in children with refractory disease and relapse. There is no consensus on the salvage therapy approach; however, HSCT appears to be the optimal choice.