Chemoimmunotherapy Combined With Autologous NK Cell Therapy for Pediatric Patients With Refractory and Relapsed High-Risk Neuroblastoma and Ganglioneuroblastoma

Neuroblastoma (NB) is a malignant neoplasm of the sympathetic nervous system, occurring in 1 in 8,000 live births, accounting for 6-10% of all childhood malignant neoplasms and responsible for 12-15% of mortality -, making it the most common and life-threatening extracranial tumor in childhood. Patients with stage 4 high-risk NB is the subgroup with the poorest prognosis. Within this group, two subgroups with an extremely unfavorable disease course are distinguished: patients with a poor response to the induction phase of therapy (refractory disease) and patients with relapsed or progressive disease. Nowadays, 10-15% of patients show a poor end-induction response, whereas achieving a good end-induction response associated with better long-term survival. Improvement of the response to induction therapy may contribute to better treatment outcomes in newly diagnosed high-risk NB patients and can be achieved by intensification of the induction phase to decrease the number of patients with refractory disease. Also intensification of the second-line therapy may contribute to better responses in patients with relapsed and progressive disease. Protocol aimed to overcome heterogeneous tumor drug resistance through the synergistic interaction of cytostatic and immunobiological agents in combination with NK cell therapy. This approach combines cytotoxic agents with anti-GD2 monoclonal antibodies (mAb) to enhance antitumor activity. Cultured, ex vivo-activated autologous NK cells are infused to compensate for effector cell depletion during therapy and to augment antibody-dependent cellular cytotoxicity (ADCC), potentially improving clinical outcomes. This comprehensive approach opens novel prospects for enhancing treatment efficacy in patients with refractory and relapsed high-risk NB. The expected outcomes of this protocol include a significant increase in therapeutic efficacy indicators - objective response rate (ORR), overall survival (OS), progression-free survival (P