Treatment of high-risk neuroblastoma

Autologous or allogeneic hematopoietic stem cells transplantation combined with high-dose chemotherapy for refractory neuroblastoma: A protocol for systematic review and meta-analysis

BACKGROUND

Neuroblastoma is a common solid malignant tumor in children. Despite the development of new treatment options, the prognosis of high-risk neuroblastoma patients is still poor. High-dose chemotherapy and hematopoietic stem cell (HSC) transplantation might improve survival of patients with refractory neuroblastoma. In this study, we aimed to summarize the efficacy of autologous or allogeneic HSC transplantation combined with high-dose chemotherapy for patients with refractory neuroblastoma through the meta-analysis.

METHODS AND ANALYSIS

Relevant clinical trials of autologous or allogeneic HSC transplantation for the treatment refractory neuroblastoma patients will be searched in Web of Science, Cochrane Library, PubMed, Google Scholar, Embase, Medline, China National Knowledge Infrastructure, China Scientific Journal Database, Chinese Biomedical Literature Database and Wanfang Database from their inception to December 2020. Two researchers will perform data extraction and risk of bias assessment independently. The clinical outcomes including tumor response, overall survival, event-free survival (EFS), quality of life (QoL) and adverse events, were systematically evaluated by using Review Manager 5.3 and Stata 14.0 statistical software.

RESULTS

The results of this study will provide high-quality evidence for the effect of autologous or allogeneic HSC transplantation combined with high-dose chemotherapy on tumor response, survival, and QoL in patients with refractory neuroblastoma.

CONCLUSIONS

The conclusions of this meta-analysis will be published in a peer-reviewed journal, and provide more evidence-based guidance in clinical practice.

Opportunities and challenges of circulating biomarkers in neuroblastoma

Molecular analysis of nucleic acid and protein biomarkers is becoming increasingly common in paediatric oncology for diagnosis, risk stratification and molecularly targeted therapeutics. However, many current and emerging biomarkers are based on analysis of tumour tissue, which is obtained through invasive surgical procedures and in some cases may not be accessible. Over the past decade, there has been growing interest in the utility of circulating biomarkers such as cell-free nucleic acids, circulating tumour cells and extracellular vesicles as a so-called liquid biopsy of cancer. Here, we review the potential of emerging circulating biomarkers in the management of neuroblastoma and highlight challenges to their implementation in the clinic.

Preclinical Pharmacokinetics and Dosimetry Studies of 124I/131I-CLR1404 for Treatment of Pediatric Solid Tumors in Murine Xenograft Models

Cancer is the second leading cause of death for children between the ages of 5 and 14 y. For children diagnosed with metastatic or recurrent solid tumors, for which the utility of external-beam radiotherapy is limited, the prognosis is particularly poor. The availability of tumor-targeting radiopharmaceuticals for molecular radiotherapy (MRT) has demonstrated improved outcomes in these patient populations, but options are nonexistent or limited for most pediatric solid tumors. 18-(p-iodophenyl)octadecylphosphocholine (CLR1404) is a novel antitumor alkyl phospholipid ether analog that broadly targets cancer cells. In this study, we evaluated the in vivo pharmacokinetics of ¹²⁴I-CLR1404 (CLR 124) and estimated theranostic dosimetry for ¹³¹I-CLR1404 (CLR 131) MRT in murine xenograft models of the pediatric solid tumors neuroblastoma, rhabdomyosarcoma, and Ewing sarcoma. Methods: Tumor-bearing mice were imaged with small-animal PET/CT to evaluate the whole-body distribution of CLR 124 and, correcting for differences in radioactive decay, predict that of CLR 131. Image volumes representing CLR 131 provided input for Geant4 Monte Carlo simulations to calculate subject-specific tumor dosimetry for CLR 131 MRT. Pharmacokinetics for CLR 131 were extrapolated to adult and pediatric humans to estimate normal-tissue dosimetry. In neuroblastoma, a direct comparison of CLR 124 with ¹²⁴I-metaiodobenzylguanidine (¹²⁴I-MIBG) in an MIBG-avid model was performed. Results: In vivo pharmacokinetics of CLR 124 showed selective uptake and prolonged retention across all pediatric solid tumor models investigated. Subject-specific tumor dosimetry for CLR 131 MRT presents a correlative relationship with tumor-growth delay after CLR 131 MRT. Peak uptake of CLR 124 was, on average, 22% higher than that of ¹²⁴I-MIBG in an MIBG-avid neuroblastoma model. Conclusion: CLR1404 is a suitable theranostic scaffold for dosimetry and therapy with potentially broad applicability in pediatric oncology. Given the ongoing clinical trials for CLR 131 in adults, these data support the development of pediatric clinical trials and provide detailed dosimetry that may lead to improved MRT treatment planning.