Immunotherapy in Pediatric B-Cell Acute Lymphoblastic Leukemia: Advances and Ongoing Challenges
Leukemia, most commonly B-cell acute lymphoblastic leukemia (B-ALL), accounts for about 30% of childhood cancer diagnoses. While there have been dramatic improvements in childhood ALL outcomes, certain subgroups-particularly those who relapse-fare poorly. In addition, cure is associated with significant short- and long-term side effects. Given these challenges, there is great interest in novel, targeted approaches to therapy. A number of new immunotherapeutic agents have proven to be efficacious in relapsed or refractory disease and are now being investigated in frontline treatment regimens. Blinatumomab (a bispecific T-cell engager that targets cluster of differentiation [CD]-19) and inotuzumab ozogamicin (a humanized antibody-drug conjugate to CD22) have shown the most promise. Chimeric antigen receptor T (CAR-T) cells, a form of adoptive immunotherapy, rely on the transfer of genetically modified effector T cells that have the potential to persist in vivo for years, providing ongoing long-term disease control. In this article, we discuss the clinical biology and treatment of B-ALL with an emphasis on the role of immunotherapy in overcoming the challenges of conventional cytotoxic therapy. As immunotherapy continues to move into the frontline of pediatric B-ALL therapy, we also discuss strategies to address unique side effects associated with these agents and efforts to overcome mechanisms of resistance to immunotherapy.
Catheter-Directed Thrombolysis for Neonatal IVC and Bilateral Renal Vein Thrombosis: A Case Report
Renal vein thrombosis is the most common non-catheter-associated venous thromboembolism event in neonates, accounting for up to 20% of cases. Although mortality rates are lower than a variety of other forms of pediatric thrombosis, renal vein thrombi are associated with significant short-term and long-term sequelae. This report presents the case of a full-term neonate presenting with bilateral renal vein thrombosis with inferior vena cava involvement treated with catheter-directed thrombolysis. This case report intends to highlight the value of a multidisciplinary approach to pediatric venous thromboembolism and to outline relevant procedural details and current laboratory and imaging monitoring of catheter-directed thrombolysis.
High-dose methotrexate dosing strategy in primary central nervous system lymphoma
The backbone induction therapy for primary central nervous system lymphoma (PCNSL) is high dose methotrexate (HD-MTX) and rituximab, which can be combined with other chemotherapeutic agents. The optimal dose of HD-MTX remains unclear, as doses between 3 and 8â€‰g/m2 have been shown to be effective. In this retrospective study, HD-MTX dosed at 3-5â€‰g/m2 demonstrated an overall response of 81.8%, with 11 (50%) complete responses. The median overall survival was not met at 29â€‰months and median progression free survival was 12.5â€‰months.There were two discontinuations due to nephrotoxicity. The most common adverse event was hepatotoxicity (18.5%), with no treatment-related mortality events observed.Overall, HD-MTX dosed at 3-5â€‰g/m2 demonstrated similar efficacy and lower toxicity compared to higher doses in PCNSL patients. Reducing the initial HD-MTX dose may help ensure tolerability and completion of induction therapy, especially in patients with co-morbidities or older age who have poorer outcomes.