Improved survival of children with advanced neuroblastoma treated by intensified therapy including myeloablative chemotherapy with stem cell transplantation: a retrospective analysis from the Tohoku Neuroblastoma Study Group

Survival Benefit of Myeloablative Therapy with Autologous Stem Cell Transplantation in High-Risk Neuroblastoma: A Systematic Literature Review

BACKGROUND

Multimodal treatment of newly diagnosed high-risk neuroblastoma (HRNB) includes induction chemotherapy, consolidation with myeloablative therapy (MAT) and autologous stem cell transplantation (ASCT), followed by anti-disialoganglioside 2 (GD2) immunotherapy, as recommended by the Children's Oncology Group (COG) and the Society of Paediatric Oncology European Neuroblastoma (SIOPEN). Some centres proposed an alternative approach with induction chemotherapy followed by anti-GD2 immunotherapy, without MAT+ASCT.

OBJECTIVE

The aim of this systematic literature review was to compare survival outcomes in patients with HRNB treated with or without MAT+ASCT and with or without subsequent anti-GD2 immunotherapy.

PATIENTS AND METHODS

The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. MEDLINE via PubMed and EMBASE databases were systematically searched for randomised controlled trials (RCT) and observational comparative studies in patients with HRNB using search terms for 'neuroblastoma' and ('myeloablative therapy' OR 'stem cell transplantation'). Reporting of at least one survival outcome [event-free survival (EFS), progression-free survival, relapse-free survival and/or overall survival (OS)] was required for inclusion. Outcomes from RCTs were synthesized in meta-analysis, while meta-analysis of non-RCTs was not planned owing to expected heterogeneity.

RESULTS

Literature searches produced 2587 results with 41 publications reporting 34 comparative studies included in the review. Of these, 7 publications reported 4 RCTs, and 34 publications reported 30 non-RCT studies. Studies differed with respect to included populations, induction regimen, response to induction, additional treatments and transplantation procedures. Subsequent treatments of relapse were rarely reported and could not be compared. In the meta-analysis, EFS was in favour of MAT+ASCT over conventional chemotherapy or no further treatment [hazard ratio (HR) = 0.78, 95% confidence interval (CI) 0.67-0.91, p = 0.001] with a trend favouring MAT+ASCT for OS (HR = 0.86, 95% CI 0.73-1.00, p = 0.05). Tandem MAT+ASCT was found to improve EFS compared with the single procedure, with improvement in both EFS and OS in patients treated with anti-GD2 therapy. Non-RCT comparative studies were broadly consistent with evidence from the RCTs; however, not all reported survival benefits of MAT+ASCT (single or tandem). Limited comparative evidence on treatment without MAT+ASCT in patients treated with anti-GD2 immunotherapy suggests an increased risk of relapse. In relapsed patients, MAT+ASCT appears to improve OS, but evidence remains scarce.

CONCLUSIONS

Survival benefits in patients treated with MAT+ASCT confirm that the procedure should remain an integral part of multimodal therapy. In patients treated with anti-GD2 immunotherapy, limited evidence suggests that omitting MAT+ASCT is associated with an increased risk of relapse, and therefore, a change in clinical practice can currently not be recommended. Evidence suggests the use of tandem MAT+ASCT compared with the single procedure, with greater benefits observed in patients treated with anti-GD2 immunotherapy. Limited evidence also suggests improved survival following MAT+ASCT in relapsed patients, which needs to be viewed in light of emerging chemoimmunotherapy in this setting.

Treatment and outcomes of high-risk neuroblastoma in Southeast Asia: a single-institution experience and review of the literature

INTRODUCTION

In Europe and North America, the majority of children with high-risk neuroblastoma survive the disease. Elsewhere, the treatment outcomes are poor.

METHODS

A retrospective review of children treated for high-risk neuroblastoma in a single institution in Singapore from 2007 to 2019 was carried out. Treatment consisted of intensive chemotherapy, surgery aimed at gross total resection of residual disease after chemotherapy, consolidation with high-dose therapy followed by autologous stem cell rescue, and radiotherapy to the primary and metastatic sites followed by maintenance treatment with either cis-retinoic acid or anti-disialoganglioside monoclonal antibody therapy. Survival data were examined on certain clinical and laboratory factors.

RESULTS

There were 57 children (32 male) treated for high-risk neuroblastoma. Their mean age was 3.9 (range 0.7-14.9) years. The median follow-up time was 5.5 (range 1.8-13.0) years for the surviving patients. There were 31 survivors, with 27 patients surviving in first remission, and the five-year overall survival and event-free survival rates were 52.5% and 47.4%, respectively. On log-rank testing, only the group of 17 patients who were exclusively treated at our centre had a survival advantage. Their five-year overall survival rate compared to patients whose initial chemotherapy was done elsewhere was 81.6% versus 41.1% (P = 0.011), and that of event-free survival was 69.7% versus 36.1% (P = 0.032). Published treatment results were obtained from four countries in Southeast Asia with five-year overall survival rates from 13.5% to 28.2%.

CONCLUSION

Intensified medical and surgical treatment for high-risk neuroblastoma proved to be effective, with superior survival rates compared to previous data from Southeast Asia.

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.

Feasibility of sequential high-dose chemotherapy in advanced pediatric solid tumors

The purpose of this study was to evaluate the feasibility and tumor response of 3 cycles of sequential high-dose chemotherapy (HDCT) in advanced pediatric solid tumor patients. Medical records of 11 children who underwent 2 consequent courses of reduced conditioning HDCT followed by final HDCT with autologous HSC infusion were reviewed in a retrospective manner. Each median time to an absolute neutrophil count > 0.5 x 10(9)/L was 12, 13, and 12 days. Major toxic reactions were fever, infection, and vomiting. One patient experienced transplantation-related mortality. Nine patients showed complete and partial responses to the therapy at 6 months follow-up after final HDCT. Finally, 6 patients are alive without evidence of disease at median follow-up of 24 months. Even though it is a preliminary result, the authors think that this treatment could be a feasible treatment option for advanced pediatric solid tumor patients.

Late recurrence in pediatric cancer: a report from the Childhood Cancer Survivor Study

BACKGROUND

An increasing percentage of childhood cancer patients are surviving their disease, but there is limited research on late recurrence. We sought to estimate late recurrence rates for the most common pediatric cancers and to determine risk factors for late recurrence.

METHODS

The incidence of late recurrences, or first recurrences that occurred more than 5 years after diagnosis, was analyzed for the most common pediatric cancers using data from the Childhood Cancer Survivor Study, a retrospective cohort of 5-year survivors of childhood and adolescent cancers who were diagnosed between 1970 and 1986. A total of 12,795 survivors with no history of recurrence within 5 years after their original cancer diagnosis were included in the analysis, with a total of 217,127 person-years of follow-up. Cumulative incidence of late recurrence at 5, 10, 15, and 20 years after diagnosis was calculated using death as a competing risk. Adjusted relative rates of late recurrence were obtained using multivariable Poisson regression. All statistical tests were two-sided.

RESULTS

Overall, 5-year survivors of pediatric cancers experienced a cumulative incidence of recurrent disease of 4.4%, 5.6%, and 6.2% at 10, 15, and 20 years, respectively. Cumulative incidence varied by diagnosis: Survivors of Ewing sarcoma and astrocytoma had the highest 20-year cumulative incidences at 13.0% (95% confidence interval [CI] = 9.4 to 16.5) and 14.4% (95% CI = 12.3 to 16.6), respectively. In multivariable analysis, the greatest risk factors for late recurrence included diagnosis, combination treatment with chemotherapy and radiation, earlier treatment era, and fewer years since diagnosis (P < .001 for all).

CONCLUSION

Late recurrence is a risk for some pediatric cancers. By understanding diagnosis-specific risks, patients, families, and their medical providers can be better informed of the probability of cure.

Prognostic influence of minimal residual disease detected by flow cytometry and peripheral blood stem cell transplantation by CD34+ selection in childhood advanced neuroblastoma

OBJECTIVE

To determine whether neuroblastoma (NB) minimal residual disease (MRD) in bone marrow (BM) detected by flow cytometry could predict prognosis and whether tumor cell purging by CD34(+) cell selection prior to transplantation will impact on disease-free survival.

METHODS

NB MRD in BM was evaluated by flow cytometry with CD45-FITC-/CD81-PE+/CD56-PECy5+ monoclonal antibodies cocktail. Peripheral blood stem cell (PBSC) was enriched via positive CD34(+) cell selection by magnetic-activated cell separation system (MACS).

RESULTS

Eleven of 31 patients with CD45(-)/CD81+/CD56+ cells by flow cytometry at diagnosis became negative after an average of four courses of chemotherapy. All 11 patients remained alive without evidence of disease. Thirteen of the 20 patients with positive MRD relapsed and 1 patient died from disease (mean 25.8 months). There was a significant difference between these two groups. MRD in BM was tested before PBSC transplantation (PBSCT) for 19 NB patients. Fourteen was negative, 4 of them relapsed and 10 patients remained alive without evidence of disease. Another 5 patients with positive MRD, all of them relapsed (mean 17 months after PBSCT) with a significant difference between these two groups. Fourteen of 19 PBSC were purged with CD34(+) selection procedure. Six of 14 relapsed (mean 18.43 months after PBSCT). Five patients did not purge for CD34(+) selection, and 3 of them relapsed with no significant difference between these two groups.

CONCLUSIONS

Positive MRD in BM after an average of four courses of chemotherapy and before PBSCT is an unfavorable factor for stage IV NB. CD34(+) selection purging for PBSCT may not improve the prognosis for children with neuroblastoma in advanced stage.

Proapoptotic compound ARC targets Akt and N-myc in neuroblastoma cells

We have previously described the identification of a nucleoside analog transcriptional inhibitor ARC (4-amino-6-hydrazino-7-beta-D-ribofuranosyl-7H-pyrrolo[2,3-d]-pyrimidine-5-carboxamide) that was able to induce apoptosis in cancer cell lines of different origin. Here, we report the characterization of ARC on a panel of neuroblastoma cell lines. We found that these cell lines were more than 10-fold sensitive to ARC than to the well-known nucleoside analog DRB (5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole), and that ARC-induced apoptosis proceeds through mitochondrial injury. Also, we observed that ARC-mediated cell death was accompanied by caspase-3 cleavage and repression of antiapoptotic proteins such as Mcl-1 and survivin. Conversely, we found that overexpression of Mcl-1-protected neuroblastoma cell line NB-1691 from ARC-induced apoptosis. Furthermore, we found that while ARC inhibited the phosphorylation of Akt Ser-473 in multiple cancer cell lines, forced expression of myristoylated Akt promoted resistance to ARC-induced apoptosis in neuroblastoma cells. In addition, we observed that ARC was able to downregulate the protein levels of N-myc, a commonly amplified oncogene in neuroblastomas, and Akt protected N-myc from ARC-induced downregulation. These data suggest that ARC may antagonize different antiapoptotic pathways and induce apoptosis in neuroblastoma cells via multiple mechanisms. Overall, ARC could represent an attractive candidate for anticancer drug development against neuroblastomas.

Retrospective analysis of peripheral blood stem cell transplantation for the treatment of high-risk neuroblastoma

Disease relapse after autologous peripheral blood stem cell transplantation (APBSCT) is the main cause of treatment failure in high-risk neuroblastoma (NBL). To reduce relapse, various efforts have been made such as CD34+ selection and double APBSCT. Here the authors reviewed the clinical features and outcomes of highrisk NBL patients and analyzed their survival. The medical records of 36 patients with stage III or IV NBL who underwent APBSCT at Seoul National University Children's Hospital between May 1996 and May 2004 were reviewed. Total 46 APBSCTs were performed in 36 patients. Disease free survival (DFS) and overall survival of all patients were 47.7% and 68.8%, respectively. The patients were allocated to three groups according to the APBSCT type. The DFS of CD34+ non-selected single APBSCT patients (N=13), CD34+ selected single APBSCT patients (N=14), and CD34+ selected double APBSCT patients (N=9) were 55.6%, 40.6%, and 50.0%, respectively, which were not significantly different. Thus the survival was not found to be affected by CD34+ selection or transplantation number. To improve long-term survival, various efforts should be made such as chemotherapy dose intensification, more effective tumor purging, and control of minimal residual disease via the use of differentiating and immune-modulating agents.

Feasibility and response to induction chemotherapy intensified with high-dose methotrexate for young children with newly diagnosed high-risk disseminated medulloblastoma

PURPOSE

To evaluate the feasibility of and response rate to an intensified induction chemotherapy regimen for young children with newly diagnosed high-risk or disseminated medulloblastomas.

PATIENTS AND METHODS

From January 1997 to March 2003, 21 patients with high-risk or disseminated medulloblastoma were enrolled. After maximal surgical resection, patients were treated with five cycles of vincristine (0.05 mg/kg/wk x three doses per cycle for three cycles), cisplatin (3.5 mg/kg per cycle), etoposide (4 mg/kg/d x 2 days per cycle), cyclophosphamide (65 mg/kg/d x 2 days per cycle) with mesna, and methotrexate (400 mg/kg per cycle) with leucovorin rescue. Following induction chemotherapy, eligible patients underwent a single myeloablative chemotherapy cycle with autologous stem-cell rescue.

RESULTS

Significant toxicities of this intensified regimen, including gastrointestinal and infectious toxicities, are described. Among the 21 patients enrolled, there were 17 complete responses (81%), two partial responses, one stable disease, and one progressive disease. The 3-year event-free survival and overall survival are 49% (95% CI, 27% to 72%) and 60% (95% CI, 36% to 84%), respectively.

CONCLUSION

This intensified induction chemotherapy regimen is feasible and tolerable. With the majority of patients with disseminated medulloblastoma having M2 or M3 disease at diagnosis, the encouraging high response rate of this intensified induction regimen suggests that such an addition of methotrexate should be explored in future studies.

A novel dysfunctional p53 mutation in the human neuroblastoma cell line TGW

Mutations of p53 are rare in primary and advanced neuroblastomas. The p53 gene was studied in a TGW cell line established from a TNB1 xenograft, derived from metastasized neuroblastoma. The p53 protein level in TGW was elevated at baseline. Treatment with doxorubicin to induce genotoxic stress neither altered the p53 protein level nor induced p21 protein within 24 hours. DNA sequencing analysis revealed a novel triplet deletion mutation at codon 282 (R282del) of the p53 gene, a mutation also found in TNB1, indicating that the mutation occurred in the relapsed tumor. The mutant was incapable of transactivation and had no effect on the transactivational activity of the wild-type p53 gene product in reporter assays using a plasmid possessing a p53 responsive element of p21, bax or mdm2. These results suggest that the mutant p53R282del found in TGW is a non-functional mutant and has no dominant negative nature.

The impact of gross total resection on local control and survival in high-risk neuroblastoma

BACKGROUND/PURPOSE

Gross total resection of the primary tumor in treatment of high-risk neuroblastoma remains controversial. Furthermore, there are few reports of the effect of primary tumor resection on local control as opposed to overall survival. The authors reviewed their institutional experience to assess the effect of primary tumor resection on local control and overall survival.

METHODS

A total of 141 patients were treated on protocol between November 1, 1979 and June 25, 2002 and are the subject of this report. Gross total resection was assessed by review of operative notes, postoperative computerized axial tomograms, and postoperative meta-iodobenzyl guanidine (MIBG)1 scans when available.

RESULTS

The median age was 3.3 years, and all patients were International Neuroblastoma Staging System (INSS) stage 4 with 79% having metastases to cortical bone. The primary site was the adrenal gland in 74%, the central abdominal compartment in 13%, the posterior mediastinum in 7%, and other sites in 6%. Gross total resection was accomplished in 103 (73%) but was more than 90% for the last 3 protocols. Five kidneys were lost overall. The probability of local progression was 50% in unresected patients compared with 10% in patients undergoing gross total resection (P <.01). Overall survival rate in resected patients was 50% compared with 11% in unresected patients (P <.01).

CONCLUSIONS

Our data indicate that local control and overall survival rate are correlated with gross total resection of the primary tumor in high-risk neuroblastoma. Gross total resection should be part of the management of stage 4 neuroblastoma in patients greater than 1 year of age.