Incidence, Survival, and Treatment of Localized and Metastatic Neuroblastoma in Germany 1979-2015

Characteristics, treatments, and outcomes of adolescents and adults with neuroblastoma: a retrospective study in China

Background

Neuroblastoma (NB) is rare in adolescents and adults, resulting in limited availability of data.

Objectives

We comprehensively investigated the characteristics, treatments, and outcomes of adolescent and adult patients with NB, aiming to provide a more in-depth insight into this disease.

Design

A retrospective, single-center study.

Methods

We retrieved and analyzed the medical data of patients with NB aged 10 years or older at diagnosis who were treated at Sun Yat-sen University Cancer Center between June 2005 and January 2024.

Results

Sixty-five patients (30 males and 35 females) were enrolled, with a median age of 20 years (interquartile range, 14-26 years), including 27 patients aged 10-18 years and 38 patients aged >18 years. Most patients were classified as M-stage disease (n = 40, 61.5%), high-risk (n = 42, 64.6%), and poorly differentiated NB (n = 27, 41.5%). Additionally, 3 (6.7%) patients had MYCN amplification, and 5 (25%) had ALK mutations. The genomic landscape revealed that mutations in the cell cycle and DNA repair pathways are related to chemotherapy sensitivity. After induction therapy, 34 (52.3%) patients achieved complete response (CR). The 5-year progression-free survival (PFS) and overall survival (OS) rates were 33.1% ± 6.9% and 55.1% ± 7.6%, respectively. Patients who achieved CR after induction therapy had superior PFS (p = 0.009), with 5-year PFS rates of 44.0% ± 10.6% compared to 18.5% ± 8.5% in non-CR patients.

Conclusion

Adolescent and adult patients with NB exhibit distinct characteristics, less chemotherapy sensitivity, and poorer outcomes compared to pediatric patients. Achieving CR after induction therapy is associated with better outcomes. Further investigation for new therapies is required.

Integrating neuron-specific enolase and venous-phase enhanced computed tomography radiomics for improved survival prediction in high-risk neuroblastoma: a two-center study

BACKGROUND

High-risk neuroblastoma is associated with a poor prognosis, making it crucial to identify patients within this group who face an even higher risk of adverse outcomes.

OBJECTIVE

To determine if integrating clinical indicators and venous-phase enhanced computed tomography radiomics features could improve the prediction of overall survival in high-risk neuroblastoma.

MATERIALS AND METHODS

We retrospectively included high-risk neuroblastoma patients treated at a primary institution, randomly stratifying them into a training set (70%) and a test set (30%). Univariate and multivariate Cox regression analyses were used to identify independent clinical risk factors. We then extracted radiomics features from venous-phase enhanced computed tomography images. Clinical risk factors, radiomics score, and combined model were evaluated in the training, test, and external validation sets.

RESULTS

The training, test, and validation sets included 70, 30, and 40 patients, respectively. Neuron-specific enolase was identified as the independent clinical risk factor, with concordance indices of 0.616, 0.627, and 0.595 in the training, test, and validation sets, respectively. The radiomics score achieved concordance indices of 0.699, 0.690, and 0.684 in the training, test, and validation sets, respectively. The combined model showed concordance indices of 0.730, 0.707, and 0.690 in the training, test, and validation sets, respectively. The combined model predicted 5-year overall survival with an area under the receiver operating characteristic curve of 0.780 in the training set, 0.742 in the test set, and 0.710 in the validation set.

CONCLUSION

Combining neuron-specific enolase and venous-phase enhanced computed tomography radiomics improves survival prediction in high-risk neuroblastoma.

Individual risk and prognostic value prediction by interpretable machine learning for distant metastasis in neuroblastoma: A population-based study and an external validation

PURPOSE

Neuroblastoma (NB) is a childhood malignancy with a poor prognosis and a propensity for distant metastasis (DM). We aimed to establish machine learning (ML) based model to accurately predict risk of DM and prognosis of NB patients with DM.

METHODS

We analyzed NB patients from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2020. Univariate and multivariate logistic analysis were employed to select meaning variables. Recursive Feature Elimination (RFE) method based on 6 ML algorithms was utilized in feature selection. To construct predictive model, 13 ML algorithms were evaluated by area under the operating characteristic curve (AUC), accuracy, sensitivity, specificity, precision, cross-entropy, Brier scores, Balanced Accuracy and F-beta score. An optimal ML model was constructed to predict DM, and the predictive results were explained by SHapley Additive exPlanations (SHAP) framework. Meanwhile, 101 ML algorithm combinations were developed to select the best model with highest C-index to predict prognosis of NB patients with DM.

RESULTS

A total of 1,668 NB patients from SEER database was consecutively enrolled. We identified that tumor primary site, grade, surgery type, regional lymph nodes, radiotherapy and chemotherapy are significant risk factors for DM. CatBoost model was selected as the best prediction model, and AUC was 0.846 (95 %CI: [0.804,0.899]), 0.834 (95 %CI: [0.796,0.873]) and 0.813 (95 %CI: [0.776,0.852]) in training, internal test and external test sets, with 0.777 accuracy, 0.839 sensitivity, 0.72 specificity and 0.731 precision in training set. Grade, chemotherapy and radiotherapy had the greatest effects on DM according to SHAP results. For prognosis prediction, "RSF + GBM" algorithm was the best prognostic model with C-index of 0.656, 0.611 and 0.629 in training, internal test and external test sets.

CONCLUSIONS

Our ML models demonstrate excellent accuracy and reliability, offering more precise personalized metastasis diagnosis and prognostic prediction to NB patients.

The anti-GD2 monoclonal antibody naxitamab plus GM-CSF for relapsed or refractory high-risk neuroblastoma: a phase 2 clinical trial

In this single-arm, non-randomized, phase 2 trial (NCT03363373), 74 patients with relapsed/refractory high-risk neuroblastoma and residual disease in bone/bone marrow (BM) received naxitamab on Days 1, 3, and 5 (3 mg/kg/day) with granulocyte-macrophage colony-stimulating factor (Days -4 to 5) every 4 weeks, until complete response (CR) or partial response (PR) followed by 5 additional cycles every 4 weeks. Primary endpoint in the prespecified interim analysis was overall response (2017 International Neuroblastoma Response Criteria). Among 26 responders (CR + PR) in the efficacy population (N = 52), 58% had refractory disease, and 42% had relapsed disease. Overall response rate (ORR) was 50% (95% CI: 36-64%), and CR and PR were observed in 38% and 12%, respectively. With the 95% CI lower limit for ORR exceeding 20%, the primary endpoint of overall response was met. Patients with evaluable bone disease had a 58% (29/50) bone compartment response (CR, 40%; PR, 18%). BM compartment response was 74% (17/23; CR, 74%). One-year overall survival and progression-free survival (secondary endpoints) were 93% (95% CI: 80-98%) and 35% (95% CI: 16-54%), respectively. Naxitamab-related Grade 3 adverse events included hypotension (58%) and pain (54%). Overall, naxitamab demonstrated clinically meaningful efficacy with manageable safety in patients with residual neuroblastoma in bone/BM.

Targeting MYCN upregulates L1CAM tumor antigen in MYCN-dysregulated neuroblastoma to increase CAR T cell efficacy

Current treatment protocols have limited success against MYCN-amplified neuroblastoma. Adoptive T cell therapy presents an innovative strategy to improve cure rates. However, L1CAM-targeting CAR T cells achieved only limited response against refractory/relapsed neuroblastoma so far. We investigated how oncogenic MYCN levels influence tumor cell response to CAR T cells, as one possible factor limiting clinical success. A MYCN-inducible neuroblastoma cell model was created. L1CAM-CAR T cell effector function was assessed (activation markers, cytokine release, tumor cytotoxicity) after coculture with the model or MYCN-amplified neuroblastoma cell lines. RNA sequencing datasets characterizing the model were compared to publicly available RNA/proteomic datasets. MYCN-directed L1CAM regulation was explored using public ChIP-sequencing datasets. Synergism between CAR T cells and the indirect MYCN inhibitor, MLN8237, was assessed in vitro using the Bliss model and in vivo in an immunocompromised mouse model. Inducing high MYCN levels in the neuroblastoma cell model reduced L1CAM expression and, consequently, L1CAM-CAR T cell effector function in vitro. Primary neuroblastomas possessing high MYCN levels expressed lower levels of both the L1CAM transcript and L1CAM tumor antigen. MLN8237 treatment restored L1CAM tumor expression and L1CAM-CAR T cell effector function. Combining MLN8237 and L1CAM-CAR T cell treatment synergistically enhanced MYCN-overexpressing tumor cytotoxicity in vitro and in vivo concomitant with severe in vivo toxicity. We identify target antigen downregulation as source of resistance against L1CAM-CAR T cells in MYCN-driven neuroblastoma cells. These data suggest that L1CAM-CAR T cell therapy combined with pharmacological MYCN inhibition may benefit patients with MYCN-amplified neuroblastoma.

International consensus statement on the diagnosis and management of phaeochromocytoma and paraganglioma in children and adolescents

Phaeochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumours that arise not only in adulthood but also in childhood and adolescence. Up to 70-80% of childhood PPGL are hereditary, accounting for a higher incidence of metastatic and/or multifocal PPGL in paediatric patients than in adult patients. Key differences in the tumour biology and management, together with rare disease incidence and therapeutic challenges in paediatric compared with adult patients, mandate close expert cross-disciplinary teamwork. Teams should ideally include adult and paediatric endocrinologists, oncologists, cardiologists, surgeons, geneticists, pathologists, radiologists, clinical psychologists and nuclear medicine physicians. Provision of an international Consensus Statement should improve care and outcomes for children and adolescents with these tumours.

Tracking changes in image-defined risk factors during neoadjuvant chemotherapy and their predictive value for surgical outcomes based on the International Neuroblastoma Surgical Report Form

BACKGROUND

The capacity of presurgical image-defined risk factors (IDRFs) to predict secondary surgical outcomes in patients with neuroblastoma is controversial.

METHODS

The International Neuroblastoma Surgical Report Form (INSRF) was employed to retrospectively collect the clinical data of 53 patients diagnosed with neuroblastoma at our hospital from April 2014 to April 2020. IDRFs were identified at the time of diagnosis and reassessed during the course of neoadjuvant chemotherapy. Various statistical tests were used to evaluate the correlation between IDRFs and secondary surgical outcomes.

RESULTS

A total of 195 IDRFs were identified. Notably, by two courses of neoadjuvant chemotherapy, the number of "two body compartments," "intraspinal tumor extension," and "trachea-compressing" IDRFs decreased significantly (p = .001). The primary tumor volumes and the number of IDRFs decreased significantly by four courses of neoadjuvant chemotherapy, especially in "intraspinal tumor extension" IDRFs (p = .034). The median number of IDRF per patient was four (interquartile range [IQR]: 1-5) at diagnosis, which diminished to one (IQR: 1-3) subsequent to neoadjuvant chemotherapy. The presence of preoperative IDRFs was not associated with surgical complications (p = .286) or the extent of surgery (p = .188). However, the number of preoperative IDRFs linked to the extent of surgery (p = .002), not to operative complications (p = .669). Specifically, presurgery "renal vessel contact" IDRFs were predictive of surgical complications, while presurgery "infiltration of vital structures" IDRFs were associated with the extent of surgery.

CONCLUSION

The number of IDRFs decreased significantly by four courses of neoadjuvant chemotherapy. The number and type of presurgery IDRFs may predict secondary surgical outcomes, surpassing the mere consideration of their presence or absence.

Immune reconstitution after transplantation of autologous peripheral stem cells in children: a comparison between CD34+ selected and nonmanipulated grafts

BACKGROUND AND AIMS

High-dose chemotherapy (HDC) followed by autologous stem cell transplantation (ASCT) improves the prognosis in pediatric patients with several solid tumors and lymphomas. Little is known about the reconstitution of the immune system after ASCT and the influence of CD34+ cell selection on the reconstitution in pediatric patients.

METHODS

Between 1990 and 2001, 94 pediatric patients with solid tumors and lymphomas received autologous CD34+ selected or unmanipulated peripheral stem cells after HDC. CD34+ selection was carried out with magnetic microbeads. The absolute numbers of T cells, B cells and natural killer (NK) cells were measured and compared in both groups at various time points post-transplant.

RESULTS

Recovery of T cells was significantly faster in the unmanipulated group at day 30, with no significant difference later on. Reconstitution of B and NK cells was similar in both groups without significant differences at any time. The CD34+-selected group was divided into patients receiving less or more than 5.385 × 106/kg CD34+ cells. Patients in the CD34+ high-dose group displayed significantly faster reconstitutions of neutrophiles and lymphocyte subsets than the CD34+ low-dose group.

CONCLUSIONS

Engraftment and reconstitution of leukocytes, B cells and NK cells after transplantation of CD34+ selected stem cells were comparable to that in patients receiving unmanipulated grafts. T-cell recovery was faster in the unmanipulated group only within the first month. However, this delay could be compensated by transplantation of >5.385 × 106 CD34+ cells/kg. Especially for patients receiving immunotherapy after HDC large numbers of immune effector cells such as NK and T cells are necessary to mediate antibody-dependent cellular cytotoxicity. Therefore, in patients receiving autologous CD34+-selected grafts, our data emphasize the need to administer high stem cell counts.

Management of High-Risk Neuroblastoma with Soft-Tissue-Only Disease in the Era of Anti-GD2 Immunotherapy

Neuroblastoma presents with two patterns of disease: locoregional or systemic. The poor prognostic risk factors of locoregional neuroblastoma (LR-NB) include age, MYCN or MDM2-CDK4 amplification, 11q, histology, diploidy with ALK or TERT mutations, and ATRX aberrations. Anti-GD2 immunotherapy has significantly improved the outcome of high-risk (HR) NB and is mostly effective against osteomedullary minimal residual disease (MRD), but less so against soft tissue disease. The question is whether adding anti-GD2 monoclonal antibodies (mAbs) benefits patients with HR-NB compounded by only soft tissue. We reviewed 31 patients treated at SJD for HR-NB with no osteomedullary involvement at diagnosis. All tumors had molecular genetic features of HR-NB. The outcome after first-line treatment showed 25 (80.6%) patients achieving CR. Thirteen patients remain in continued CR, median follow-up 3.9 years. We analyzed whether adding anti-GD2 immunotherapy to first-line treatment had any prognostic significance. The EFS analysis using Cox models showed a HR of 0.20, p = 0.0054, and an 80% decrease in the risk of relapse in patients treated with anti-GD2 immunotherapy in the first line. Neither EFS nor OS were significantly different by CR status after first-line treatment. In conclusion, adding treatment with anti-GD2 mAbs at the stage of MRD helps prevent relapse that unequivocally portends poor survival.

Revisiting Neuroblastoma: Nrf2, NF-κB and Phox2B as a Promising Network in Neuroblastoma

Neuroblastoma is the most common solid extracranial tumor during childhood; it displays extraordinary heterogeneous clinical courses, from spontaneous regression to poor outcome in high-risk patients due to aggressive growth, metastasizing, and treatment resistance. Therefore, the identification and detailed analysis of promising tumorigenic molecular mechanisms are inevitable. This review highlights the abnormal regulation of NF-κB, Nrf2, and Phox2B as well as their interactions among each other in neuroblastoma. NF-κB and Nrf2 play a key role in antioxidant responses, anti-inflammatory regulation and tumor chemoresistance. Recent studies revealed a regulation of NF-κB by means of the Nrf2/antioxidant response element (ARE) system. On the other hand, Phox2B contributes to the differentiation of immature sympathetic nervous system stem cells: this transcription factor regulates the expression of RET, thereby facilitating cell survival and proliferation. As observed in other tumors, we presume striking interactions between NF-κB, Nrf2, and Phox2B, which might constitute an important crosstalk triangle, whose decompensation may trigger a more aggressive phenotype. Consequently, these transcription factors could be a promising target for novel therapeutic approaches and hence, further investigation on their regulation in neuroblastoma shall be reinforced.

Reaching the target dose with one single 131 I-mIBG administration in high-risk neuroblastoma: The determinant impact of the primary tumour

BACKGROUND

131 I-metaiodobenzylguanidine (131 I-mIBG) effectiveness in children with metastasised neuroblastoma (NB) is linked to the effective dose absorbed by the target; a target of 4 Gy whole-body dose threshold has been proposed. Achieving this dose often requires administering 131 I-mIBG twice back-to-back, which may cause haematological toxicity. In this study, we tried identifying the factors predicting the achievement of 4 Gy whole-body dose with a single radiopharmaceutical administration.

MATERIALS AND METHODS

Children affected by metastatic NB and treated with a high 131 I-mIBG activity (>450 MBq (megabecquerel)/kg) were evaluated retrospectively. Kinetics measurements were carried out at multiple time points to estimate the whole-body dose, which was compared with clinical and activity-related parameters.

RESULTS

Seventeen children (12 females, median age 3 years, age range: 1.5-6.9 years) were included. Eleven of them still bore the primary tumour. The median whole-body dose was 2.88 Gy (range: 1.63-4.22 Gy). Children with a 'bulky' primary (>30 mL) received a higher whole-body dose than those with smaller or surgically removed primaries (3.42 ± 0.74 vs. 2.48 ± 0.65 Gy, respectively, p = .016). Conversely, the correlation between activity/kg and the whole-body dose was moderate (R: 0.42, p = .093). In the multivariate analysis, the volume of the primary tumour was the most relevant predictor of the whole-body dose (p = .002).

CONCLUSIONS

These data suggest that the presence of a bulky primary tumour can significantly prolong the 131 I-mIBG biological half-life, effectively increasing the absorbed whole-body dose. This information could be used to model the administered activity, allowing to attain the target dose without needing a two-step radiopharmaceutical administration.

The therapeutic effect of MSCs and their extracellular vesicles on neuroblastoma

Neuroblastoma is a common inflammatory-related cancer during infancy. Standard treatment modalities including surgical interventions, high-dose chemotherapy, radiotherapy, and immunotherapy are not able to increase survival rate and reduce tumor relapse in high-risk patients. Mesenchymal stem cells (MSCs) are known for their tumor-targeting and immunomodulating properties. MSCs could be engineered to express anticancer agents (i.e., growth factors, cytokines, pro-apoptotic agents) or deliver oncolytic viruses in the tumor microenvironment. As many functions of MSCs are mediated through their secretome, researchers have tried to use extracellular vesicles (EVs) from MSCs for targeted therapy of neuroblastoma. Here, we reviewed the studies to figure out whether the use of MSCs could be worthwhile in neuroblastoma therapy or not. Native MSCs have shown a promoting or inhibiting role in cancers including neuroblastoma. Therefore, MSCs are proposed as a vehicle to deliver anticancer agents such as oncolytic viruses to the neuroblastoma tumor microenvironment. Although modified MSCs or their EVs have been shown to suppress the tumorigenesis of neuroblastoma, further pre-clinical and clinical studies are required to come to a conclusion.

Impact of BCL-2 Expression on Course of Disease in Neuroblastoma

OBJECTIVE

 The antiapoptotic BCL-2 protein has implications for maturation and differentiation of neural tissue and acts as a strong modulator of carcinogenesis in different tumors. Recent research focuses not only on its benefit as a prognostic factor, but also as a potential therapeutic target. The role of BCL-2 in neuroblastoma, the most common extracranial solid tumor in childhood, remains controversial. The aim of our study was to determine the gene expression level of BCL-2 in a large cohort of neuroblastoma patients and its correlation with clinical parameters.

METHODS

 Tumor samples and clinical data were collected from 100 neuroblastoma patients treated according to the NB2004 protocol of the German Society of Pediatric Oncology and Hematology. BCL-2 gene expression levels were measured by quantitative reverse transcription polymerase chain reaction and correlated with clinical parameters.

RESULTS

 BCL-2 expression was detected in all tumor samples. Relative BCL-2 expression levels were higher in females versus males (1.839 vs. 1.342; p = 0.0143), in patients with low versus high International Neuroblastoma Staging System stage (2.051 vs. 1.463; p = 0.0206), in nonmetastatic versus metastatic disease (1.801 vs. 1.342; p = 0.0242), as well as in patients without presurgical chemotherapy (2.145 vs. 1.402; p = 0.0016), but was not associated with overall survival and MYCN amplification.

CONCLUSION

 Our study demonstrates the ubiquitous expression of BCL-2 in neuroblastoma and suggests the possibility for targeted therapy with BCL-2 inhibitors, even in lower-stage neuroblastoma. It also underlines the need for further research on concomitant genetic alterations for a better understanding of the impact of BCL-2 on this pediatric tumor type.

Asymmetric Adrenals: Sexual Dimorphism of Adrenal Tumors

CONTEXT

Sexual dimorphism has direct consequences on the incidence and survival of cancer. Early and accurate diagnosis is crucial to improve prognosis.

OBJECTIVE

This work aimed to characterized the influence of sex and adrenal asymmetry on the emergence of adrenal tumors.

METHODS

We conducted a multicenter, observational study involving 8037 patients with adrenal tumors, including adrenocortical carcinoma (ACC), aldosterone-producing adenoma (APA), cortisol-secreting adrenocortical adenomas (CSAs), non-aldosterone-producing adrenal cortical adenoma (NAPACA), pheochromocytoma (PCC), and neuroblastoma (NB), and investigated tumor lateralization according to sex. Human adrenal tissues (n = 20) were analyzed with a multiomics approach that allows determination of gene expression, catecholamine, and steroid contents in a single sample. In addition, we performed a literature review of computed tomography and magnetic resonance imaging-based studies examining adrenal gland size.

RESULTS

ACC (n = 1858); CSA (n = 68), NAPACA (n = 2174), and PCC (n = 1824) were more common in females than in males (female-to-male ratio: 1.1:1-3.8:1), whereas NBs (n = 2320) and APAs (n = 228) were less prevalent in females (0.8:1). ACC, APA, CSA, NAPACA, and NB occurred more frequently in the left than in the right adrenal (left-to-right ratio: 1.1:1-1.8:1), whereas PCC arose more often in the right than in the left adrenal (0.8:1). In both sexes, the left adrenal was larger than the right adrenal; females have smaller adrenals than males.

CONCLUSION

Adrenal asymmetry in both sexes may be related to the pathogenesis of adrenal tumors and should be considered during the diagnosis of these tumors.

A comprehensive analysis of neuroblastoma incidence, survival, and racial and ethnic disparities from 2001 to 2019

BACKGROUND

We characterize the incidence and 5-year survival of children and adolescents with neuroblastoma stratified by demographic and clinical factors based on the comprehensive data from United States Cancer Statistics (USCS) and the National Program of Cancer Registries (NPCR).

METHODS

We analyzed the incidence of neuroblastoma from USCS (2003-2019) and survival data from NPCR (2001-2018) for patients less than 20 years old. Incidence trends were calculated by average annual percent change (AAPC) using joinpoint regression. Differences in relative survival were estimated comparing non-overlapping confidence intervals (CI).

RESULTS

We identified 11,543 primary neuroblastoma cases in USCS. Age-adjusted incidence was 8.3 per million persons [95% CI: 8.2, 8.5], with an AAPC of 0.4% [95% CI: -0.1, 0.9]. Five-year relative survival from the NPCR dataset (n = 10,676) was 79.7% [95% CI: 78.9, 80.5]. Patients aged less than 1 year had the highest 5-year relative survival (92.5%). Five-year relative survival was higher for non-Hispanic White patients (80.7%) or Hispanic patients (80.8%) compared to non-Hispanic Black patients (72.6%).

CONCLUSION

Neuroblastoma incidence was stable during 2003-2019. Differences in relative survival exist by sex, age, race/ethnicity, and stage; patients who were male, older, non-Hispanic Black, or with distant disease had worse survival. Future studies could seek to assess the upstream factors driving disparities in survival, and evaluate interventions to address inequities and improve survival across all groups.

Temporal changes in childhood cancer incidence and survival by stage at diagnosis in Australia, 2000-2017

BACKGROUND

The Toronto Paediatric Cancer Stage Guidelines are a compendium of staging systems developed to facilitate collection of consistent and comparable data on stage at diagnosis for childhood cancers by cancer registries.

MATERIAL AND METHODS

This retrospective, observational cohort study investigated changes in stage-specific incidence and survival for children diagnosed between 2000-2008 compared to 2009-2017 using the population-based Australian Childhood Cancer Registry. Information on mortality for each patient was available to 31st December 2020. Shifts in incidence by stage were evaluated using chi-square tests, and differences in stage-specific five-year observed survival for all causes of death over time were assessed using flexible parametric models.

RESULTS

Stage was assigned according to the Toronto Guidelines for 96% (n = 7944) of the total study cohort (n = 8292). Changes in the distribution of incidence by stage between the two diagnosis periods were observed for retinoblastoma, with stage 0 increasing from 26% to 37% of cases (p = 0.02), and hepatoblastoma, with metastatic disease increasing from 22% to 39% of cases (p = 0.04). There were large gains in stage-specific survival over time for stage IV rhabdomyosarcoma (five-year adjusted mortality hazard ratio for 2009-2017 compared to 2000-2008 of 0.38, 95% CI 0.19-0.77; p = 0.01), stage M3 for medulloblastoma (HR = 0.41, 95% CI 0.21-0.79; p = 0.01) and metastatic neuroblastoma excluding stage MS (HR = 0.61, 95% CI 0.44-0.84; p < 0.01).

CONCLUSION

These results indicate that improvements in childhood cancer survival in Australia are most likely due to refined management rather than changes in stage at diagnosis, particularly for metastatic solid tumours. Wide international uptake of the Toronto Guidelines will allow comprehensive evaluation of differences in survival between countries.

[18F]MFBG PET/CT outperforming [123I]MIBG SPECT/CT in the evaluation of neuroblastoma

PURPOSE

Iodine 123 labeled meta-iodobenzylguanidine ([123I]MIBG) scan with SPECT/CT imaging is one of the most commonly used imaging modalities in the evaluation of neuroblastoma. [18F]-meta-fluorobenzylguanidine ([18F]MFBG) is a novel positron emission tomography (PET) tracer which was reported to have a similar biodistribution to [123I]MIBG. However, the experience of using [18F]MFBG PET/CT in the evaluation of patients with neuroblastoma is limited. This preliminary investigation aims to assess the efficacy of [18F]MFBG PET/CT in the evaluation of neuroblastomas in comparison to [123I]MIBG scans with SPECT/CT.

MATERIALS AND METHODS

In this prospective, single-center study, 40 participants (mean age 6.0 ± 3.7 years) with history of neuroblastoma were enrolled. All children underwent both [123I]MIBG SPECT/CT and [18F]MFBG PET/CT studies. The number of lesions and the Curie scores revealed by each imaging method were recorded.

RESULTS

Six patients had negative findings on both [123I]MIBG and [18F]MFBG studies. Four of the 34 patients (11.8%) were negative on [123I]MIBG but positive on [18F]MFBG, while 30 patients were positive on both [123I]MIBG and [18F]MFBG studies. In these 34 patients, [18F]MFBG PET/CT identified 784 lesions while [123I]MIBG SPECT/CT detected 532 lesions (p < 0.001). The Curie scores obtained from [18F]MFBG PET/CT (11.32 ± 8.18, range 1-27) were statistically higher (p < 0.001) than those from [123I]MIBG SPECT/CT (7.74 ± 7.52, range 0-26). 30 of 34 patients (88.2%) with active disease on imaging had higher Curie scores based on the [18F]MFBG study than on the [123I]MIBG imaging.

CONCLUSION

[18F]MFBG PET/CT shows higher lesion detection rate than [123I]MIBG SPECT/CT in the evaluation of pediatric patients with neuroblastoma.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov : NCT05069220 (Registered: 25 September 2021, retrospectively registered); Institute Review Board of Peking Union Medical College Hospital: ZS-2514.

Survival patterns of childhood neuroblastoma: an analysis of clinical data from Southern-Eastern European countries

The prognosis of children with neuroblastoma (NBL) can be dismal with significant variations depending on the stage and biology of the tumor. We assessed the event-free (EFS) and overall (OS) survival using harmonized data from three Southern-Eastern European (SEE) countries. Data for 520 incident NBL cases (2009-2018) were collected from Greece, Slovenia and Russia. Kaplan-Meier curves were fitted, and EFS/OS were derived from Cox proportional models by study variables including the protocol-based risk-group (low/observation, intermediate, high). Over one-third of cases were coded in the high-risk group, of which 23 children (4.4%) received treatment with anti-ganglioside 2 (GD2) mAb. Survival rates were inferior in older (OS 5-year; 1.5-4.9 years: 61%; EFS 5-year; 1.5-4.9 years: 48%) compared to children younger than 1.5 years (OS 5-year; <1.5 years: 91%; EFS 5-year; <1.5 years: 78%). Predictors of poor OS included stage 4 (hazard ratio, HR OS : 18.12, 95% confidence intervals, CI: 3.47-94.54), N-myc amplification (HR OS : 2.16, 95% CI: 1.40-3.34), no surgical excision (HR OS : 3.27, 95% CI: 1.91-5.61) and relapse/progression (HR OS : 5.46, 95% CI: 3.23-9.24). Similar unfavorable EFS was found for the same subsets of patients. By contrast, treatment with anti-GD2 antibody in high-risk patients was associated with decreased risk of death or unfavorable events (HR OS : 0.11, 95% CI: 0.02-0.79; HR EFS : 0.19, 95% CI: 0.07-0.52). Our results confirm the outstanding prognosis of the early NBL stages, especially in children <1.5 years, and the improved outcomes of the anti-GD2 treatment in high-risk patients. Ongoing high-quality clinical cancer registration is needed to ensure comparability of survival across Europe and refine our understanding of the NBL biology.

Quantitative Diffusion-Weighted MRI of Neuroblastoma

Neuroblastoma is the most common extracranial, malignant, solid tumor found in children. In more than one-third of cases, the tumor is in an advanced stage, with limited resectability. The treatment options include resection, with or without (neo-/) adjuvant therapy, and conservative therapy, the latter even with curative intent. Contrast-enhanced MRI is used for staging and therapy monitoring. Diffusion-weighted imaging (DWI) is often included. DWI allows for a calculation of the apparent diffusion coefficient (ADC) for quantitative assessment. Histological tumor characteristics can be derived from ADC maps. Monitoring the response to treatment is possible using ADC maps, with an increase in ADC values in cases of a response to therapy. Changes in the ADC value precede volume reduction. The usual criteria for determining the response to therapy can therefore be supplemented by ADC values. While these changes have been observed in neuroblastoma, early changes in the ADC value in response to therapy are less well described. In this study, we evaluated whether there is an early change in the ADC values in neuroblastoma under therapy; if this change depends on the form of therapy; and whether this change may serve as a prognostic marker. We retrospectively evaluated neuroblastoma cases treated in our institution between June 2007 and August 2014. The examinations were grouped as 'prestaging'; 'intermediate staging'; 'final staging'; and 'follow-up'. A classification of "progress", "stable disease", or "regress" was made. For the determination of ADC values, regions of interest were drawn along the borders of all tumor manifestations. To calculate ADC changes (∆ADC), the respective MRI of the prestaging was used as a reference point or, in the case of therapies that took place directly after previous therapies, the associated previous staging. In the follow-up examinations, the previous examination was used as a reference point. The ∆ADC were grouped into ∆ADCregress for regressive disease, ∆ADCstable for stable disease, and ∆ADC for progressive disease. In addition, examinations at 60 to 120 days from the baseline were grouped as er∆ADCregress, er∆ADCstable, and er∆ADCprogress. Any differences were tested for significance using the Mann-Whitney test (level of significance: p < 0.05). In total, 34 patients with 40 evaluable tumor manifestations and 121 diffusion-weighted MRI examinations were finally included. Twenty-seven patients had INSS stage IV neuroblastoma, and seven had INSS stage III neuroblastoma. A positive N-Myc expression was found in 11 tumor diseases, and 17 patients tested negative for N-Myc (with six cases having no information). 26 patients were assigned to the high-risk group according to INRG and eight patients to the intermediate-risk group. There was a significant difference in mean ADC values from the high-risk group compared to those from the intermediate-risk group, according to INRG. The differences between the mean ∆ADC values (absolute and percentage) according to the course of the disease were significant: between ∆ADCregress and ∆ADCstable, between ∆ADCprogress and ∆ADCstable, as well as between ∆ADCregress and ∆ADCprogress. The differences between the mean er∆ADC values (absolute and percentage) according to the course of the disease were significant: between er∆ADCregress and er∆ADCstable, as well as between er∆ADCregress and er∆ADCprogress. Forms of therapy, N-Myc status, and risk groups showed no further significant differences in mean ADC values and ∆ADC/er∆ADC. A clear connection between the ADC changes and the response to therapy could be demonstrated. This held true even within the first 120 days after the start of therapy: an increase in the ADC value corresponds to a probable response to therapy, while a decrease predicts progression. Minimal or no changes were seen in cases of stable disease.

Seasonality of main childhood embryonal tumours and rhabdomyosarcoma, France, 2000-2015

Few studies have investigated the seasonal patterns of embryonal tumours. Based on data from the French National Registry of Childhood Cancers, the present study aimed to investigate seasonal variations in embryonal tumour incidence rates by month of birth and by month of diagnosis. The study included 6635 primary embryonal tumour cases diagnosed before the age of 15 years over the period 2000-2015 in mainland France. Assuming monthly variations in incidence rates were homogeneous over 2000-2015, we used a Poisson regression model to test for overall heterogeneity in standardised incidence ratios (SIRs) by month of birth or diagnosis. The seasonal scan statistic method was used to detect monthly excesses or deficits of embryonal tumour cases over the whole study period. The annual reproducibility of the observed monthly variations was formally tested. An overall heterogeneity in incidence rates by month of birth was observed for rhabdomyosarcoma in boys only. Based on the month of diagnosis, a seasonality was evidenced for unilateral retinoblastoma, with a lower incidence rate in the summer (SIR_Jul-Aug  = 0.68, 95% CI = 0.52-0.87), whilst the incidence rate of rhabdomyosarcoma tended to be lower in August (SIR_Aug  = 0.68, 95% CI = 0.52-0.89). No seasonality was detected for the other embryonal tumour groups by month of birth or month of diagnosis. This study is one of the largest to have investigated the seasonality of childhood embryonal tumours. The study showed a seasonal variation in the incidence rates by month of diagnosis for unilateral retinoblastoma and rhabdomyosarcoma. Our findings are likely to reflect a delay in consultation during the summer months. However, the role of seasonally varying environmental exposures cannot be ruled out.

Long-Term Survival of Neuroblastoma Patients Receiving Surgery, Chemotherapy, and Radiotherapy: A Propensity Score Matching Study

Neuroblastoma is the most common extracranial solid malignancy in children. This study was undertaken to determine the long-term survival of neuroblastoma patients receiving conventional therapeutics (surgery, chemotherapy, and radiotherapy). The neuroblastoma patients examined were registered in the Surveillance, Epidemiology and End Results (SEER) database (1975-2016). Using propensity score matching analysis, the patients were paired by record depending on whether they received surgery, chemotherapy, or radiotherapy. Univariate and multivariate analyses of the disease-specific survival of the paired patients were performed by the log-rank test and Cox regression assay. A total of 4568 neuroblastoma patients were included in this study. During 1975-2016, the proportion of histopathological grade III/IV cases receiving surgery gradually increased, while the number of patients with tumors of grade I to IV undergoing chemotherapy or radiotherapy was stable or even decreased. After propensity score analysis, for Grade I + II and Grade III tumors, surgery obviously improved the disease-specific survival of patients, while chemotherapy was unfavorable for patient prognosis, and radiotherapy exerted no obvious effect on the patients. However, no matter what treatment was chosen, the patients with advanced-histopathological-grade tumors had a poor prognosis. Meanwhile, for all histopathological grades, the patients receiving surgery and subsequent chemotherapy or radiotherapy suffered from worsen disease-specific survival than those simply undergoing surgery. Fortunately, the negative effects of surgery, chemotherapy, or radiotherapy improved gradually over time. Surgery improved the long-term survival of the neuroblastoma patients, while chemotherapy and radiotherapy exerted an unfavorable impact on patient outcome. These results provide an important reference for the clinical treatment of neuroblastoma.

Clinical and surgical outcome differences on the basis of pathology category in cervical neuroblastic tumors

BACKGROUND

Cervical neuroblastic tumors (NTs) are rare but less aggressive cancer with an above-average survival rate. Little has been published regarding the management and surgical outcomes of patients with cervical NTs based on pathology category. This study compared and identified the preoperative characteristics of cervical NTs in different pathology categories and evaluated the outcomes of patients undergoing surgical resection.

MATERIALS AND METHODS

Upon the institutional review board's approval, a retrospective chart review was performed at Beijing Children's Hospital from April 2013 to August 2020. Demographics of patients, imaging data, lab test results, operation details and outcomes were recorded and analyzed.

RESULTS

Of 32 cervical NTs, 24(80%) were classified as neuroblastoma (NB) /ganglioneuroblastoma-nodular (GNBn) and 8(20%) as ganglioneuroblastoma-intermixed (GNBi)/ ganglioneuroma (GN). Patients with GNBi/GN were older than those with NB/GNBn (44.5 months (IQR 16-81) vs 9 months (IQR 1-47); P = 0.001). GNBi/GN patients presented more frequently with stage 1 disease compared with NB/GNBn patients (100% vs. 29.2%, P = 0.001), less frequently with tumor-related symptoms (0% vs. 70.8%, P = 0.001), artery encased tumor (0% vs. 41.7%, P = 0.035), and surgical complications (25% vs. 70.8%, P = 0.038). GNBi/GN patients were also less likely to show elevated neuron specific enolase (NSE) (12.5% vs. 79.2%, P = 0.002).

CONCLUSIONS

Cervical NB/GNBn and GNBi/GN patients had distinct characteristic clinical presentations and surgical outcomes. For children with features suggestive of benign disease (older age, asymptomatic, normal serum tumor markers) and no artery image-defined risk factors (IDRFs), upfront resection can be considered.

Kidney Failure in Children with Wilms Tumor: A Study Based on Urine Analysis and Ultrasound

BACKGROUND

Renal insufficiency is one of the inevitable complications in patients with Wilms tumor (WT). The purpose of this study was to assess the renal function in children with WT at baseline and every 3 months to 2 years.

MATERIALS AND METHODS

In a descriptive-analytical study from 2018 to 2020, 48 children with WT were included in the study. Urine creatinine (U_Cr), serum calcium (S_Cr), blood pressure (BP), estimated glomerular filtration rate (eGFR), and urinary protein (U_Pro) were evaluated at baseline and every 3 months during the study. Spot U_Ca/U_Cr and spot U_Pro/U_Cr ratio were calculated. Kidney ultrasonography was used in all patients. Independent Sample t-test and Chi-square tests were utilized to compare age and sex, respectively.

RESULTS

The mean age of patients at follow-up was 7.3 years. There was no significant difference in mean U_Cr, S_Cr, eGFR, 24-h U_Pro, U_Ca/U_Cr ratio, and spot U_Pro/U_Cr ratio at baseline and end of study (P _baseline> 0.05, P _{end of study}> 0.05). Analysis of kidney size showed a statistical association with tumor stage (P < 0.05). Comparison of the kidney size in patients showed that there is a statistically significant difference (P < 0.0001) at baseline and end of the study.

CONCLUSION

This study showed that as WT progressed, the size of the kidneys increases without any renal insufficiency. Therefore, it seems that urinalysis of patients with WT along with sonography is necessary to determine renal insufficiency and the use of ultrasound alone to determine kidney insufficiency is not recommended.

The pre-surgical factors that determine the decision to proceed to resection in children diagnosed with high-risk neuroblastoma in a resource limited setting

Surgical control has prognostic value in neuroblastoma (NB). Advanced NB is common at diagnosis in South Africa. We investigated the pre-surgery factors that influenced decisions to perform surgical resections. We included 204 patients with high-risk NB from a national retrospective study, who completed induction chemotherapy between 2000 and 2016.The median age was 32.4 months (IQR 15.1 - 53.5 months). Primary tumor resection was achieved in 76.9% of patients between 0-18 months of age, 51.8% between 18-60 months and 51.7% older than 60 months (p < 0.001). Only 43.2% of patients with distant metastatic disease had surgery done (p < 0.001). LDH was >750 U/L in 46.8% and ferritin >120 g/dL in 53.1% of those who had surgery (p = 0.005). The majority (80.4%), who had achieved post-induction metastatic complete remission (mCR), were operated, while 28.7% without mCR had surgery (p < 0.001). The long-term overall survival in patients with mCR and primary tumor resection was 36.5% compared to those with mCR without primary tumor resection (25.4%) and without mCR (≤3.0%)(p < 0.001). Age (p < 0.001), stage (p < 0.001), mCR (p < 0.001) and treatment setting (p < 0.001) were of prognostic significance. The tumor site and MYCN-amplification did not significantly predict resection rates. Post-induction mCR and stage were associated with surgical resection and five-year OS (p < 0.001) on multivariate analysis.Patients with high-risk NB who achieved mCR and had primary tumor resections are curable in limited resourced settings. Stage and post-induction mCR were significant variables that led to surgery. These variables should be included as indications in the management of metastatic NB in resource limited settings.

PET/MRI in Pediatric Neuroimaging: Primer for Clinical Practice

Modern pediatric imaging seeks to provide not only exceptional anatomic detail but also physiologic and metabolic information of the pathology in question with as little radiation penalty as possible. Hybrid PET/MR imaging combines exquisite soft-tissue information obtained by MR imaging with functional information provided by PET, including metabolic markers, receptor binding, perfusion, and neurotransmitter release data. In pediatric neuro-oncology, PET/MR imaging is, in many ways, ideal for follow-up compared with PET/CT, given the superiority of MR imaging in neuroimaging compared with CT and the lower radiation dose, which is relevant in serial imaging and long-term follow-up of pediatric patients. In addition, although MR imaging is the main imaging technique for the evaluation of spinal pathology, PET/MR imaging may provide useful information in several clinical scenarios, including tumor staging and follow-up, treatment response assessment of spinal malignancies, and vertebral osteomyelitis. This review article covers neuropediatric applications of PET/MR imaging in addition to considerations regarding radiopharmaceuticals, imaging protocols, and current challenges to clinical implementation.

Circulating Cell-Free DNA Assessment in Biofluids from Children with Neuroblastoma Demonstrates Feasibility and Potential for Minimally Invasive Molecular Diagnostics

Simple Summary

The invasive nature of surgical biopsies prevents their sequential application to monitor disease. Single biopsies fail to reflect cancer dynamics, intratumor heterogeneity, and drug sensitivities that change over time. Detection and characterization of cell-free circulating tumor DNA in biofluids from patients with solid tumors may better support disease monitoring and provide advanced molecular information for clinical decision-making toward personalized medicine. Here, we investigated the cell-free DNA characteristics in blood, bone marrow, cerebrospinal fluid, and urine provided from 84 infants and children with low-, intermediate-, or high-risk neuroblastoma. We report characteristic size distribution and concentration patterns for each biofluid to provide information to support the development of successful liquid biopsy biobanking strategies. We investigate potential correlations between disease activity and cfDNA concentration and provide strong evidence that markers specific for neuroblastoma can be detected in very small blood volumes from infants.

Abstract

Liquid biopsy strategies in pediatric patients are challenging due to low body weight. This study investigated cfDNA size distribution and concentration in blood, bone marrow, cerebrospinal fluid, and urine from 84 patients with neuroblastoma classified as low (n = 28), intermediate (n = 6), or high risk (n = 50) to provide key data for liquid biopsy biobanking strategies. The average volume of blood and bone marrow plasma provided ranged between 1 and 2 mL. Analysis of 637 DNA electropherograms obtained by Agilent TapeStation measurement revealed five different major profiles and characteristic DNA size distribution patterns for each of the biofluids. The proportion of samples containing primarily cfDNA was, at 85.5%, the highest for blood plasma. The median cfDNA concentration amounted to 6.28 ng/mL (blood plasma), 58.2 ng/mL (bone marrow plasma), 0.08 ng/mL (cerebrospinal fluid), and 0.49 ng/mL (urine) in samples. Meta-analysis of the dataset demonstrated that multiple cfDNA-based assays employing the same biofluid sample optimally require sampling volumes of 1 mL for blood and bone marrow plasma, 2 mL for cerebrospinal fluid, and as large as possible for urine samples. A favorable response to treatment was associated with a rapid decrease in blood-based cfDNA concentration in patients with high-risk neuroblastoma. Blood-based cfDNA concentration was not sufficient as a single parameter to indicate high-risk disease recurrence. We provide proof of concept that monitoring neuroblastoma-specific markers in very small blood volumes from infants is feasible.

How we approach the treatment of patients with high-risk neuroblastoma with naxitamab: experience from the Hospital Sant Joan de Déu in Barcelona, Spain

Naxitamab [humanized 3f8 (hu3F8)] is a humanized monoclonal antibody (mAb) targeting the disialoganglioside GD2. It was approved in 2020 by the United States Food and Drug Administration (FDA) in combination with granulocyte–macrophage colony-stimulating factor (GM-CSF) for treatment of pediatric and adult patients with relapsed/refractory high-risk neuroblastoma, limited to the bone or bone marrow (BM). The team at Sant Joan de Déu Children’s Hospital in Barcelona, Spain, have been using naxitamab to treat neuroblastoma under clinical trial protocols [e.g. Trial 201, and hu3F8, irinotecan, temozolomide, and sargramostim (GM-CSF) (HITS) study] and compassionate use since 2017. The team has experience with two primary regimens: naxitamab with GM-CSF only, or naxitamab in combination with irinotecan, temozolomide, and GM-CSF (chemoimmunotherapy). This article aims to provide a practical overview of the team’s experience with naxitamab to date, including preparing the treatment room and selecting the team. Adverse event management, including the use of ketamine to manage pain during anti-GD2 mAb infusions, is also discussed. We hope this will provide practical information for other health care providers considering offering this treatment.

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Immunotherapy with anti-GD2 antibodies has revolutionized the treatment of patients with high-risk neuroblastoma.

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In 2020, FDA approved naxitamab + GM-CSF for treatment of patients with R/R neuroblastoma in the bone and/or BM.

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Outpatient treatment with naxitamab-based immunotherapy may improve health-related quality of life.

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Naxitamab infusions require specific training and teamwork to prevent and efficiently manage most frequent adverse events.

The prognosis of different distant metastases pattern in malignant tumors of the adrenal glands: A population-based retrospective study

Introduction

The present existing data on the association of metastatic sites and prognosis of patients with metastatic adrenal malignancy are limited. This study aims to investigate the impact of different distant metastases pattern on the survival of patients with adrenal malignancy.

Methods

A dataset from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) 18 Registries (2000–2017) was selected for a retrospective metastatic adrenal malignancy cohort study. There was information on distribution of metastatic lesions in bone, brain, liver, and lung in the SEER database. Kaplan-Meier analysis and nomogram analyses were applied to compare the survival distribution of cases. Univariate and multivariate cox regression models were used to analyze survival outcomes.

Results

From the SEER database, a total of 980 patients with primary metastatic adrenal malignancy from 2010 to 2017 were enrolled in this cohort study. Based on the initial metastatic sites, 42.3%, 38.4%, 30.5%, and 4.9% of patients were found bone, liver, lung, and brain metastasis, respectively. Patients who had a single site of distant metastases accounted for 52.6% (515/980) and had a better overall survival (OS) and cancer-specific survival (CSS) (both P < 0.001). In contrast with the tumor arising from the cortex, the tumor from the medulla showed better survival outcomes in both OS and CSS (P < 0.001).

Conclusion

Different histological types possess various metastatic features and prognostic values. Understanding these differences may contribute to designing targeted pre-treatment assessment of primary metastatic adrenal malignancy and creating a personalized curative intervention.

High-Risk Neuroblastoma: Poor Outcomes Despite Aggressive Multimodal Therapy

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Neuroblastoma (NBL) is a highly malignant embryonal tumor that originates from the primordial neural crest cells. NBL is the most common tumor in infants and the most common extracranial solid tumor in children. The tumor is more commonly diagnosed in children of 1-4 years of age. NBL is characterized by enigmatic clinical behavior that ranges from spontaneous regression to an aggressive clinical course leading to frequent relapses and death. Based on the likelihood of progression and relapse, the International Neuroblastoma Risk Group classification system categorized NBL into very low risk, low risk, intermediate risk, and high risk (HR) groups. HR NBL is defined based on the patient's age (> 18 months), disease metastasis, tumor histology, and MYCN gene amplification. HR NBL is diagnosed in nearly 40% of patients, mainly those > 18 months of age, and is associated with aggressive clinical behavior. Treatment strategies involve the use of intensive chemotherapy (CTR), surgical resection, high dose CTR with hematopoietic stem cell support, radiotherapy, biotherapy, and immunotherapy with Anti-ganglioside 2 monoclonal antibodies. Although HR NBL is now better characterized and aggressive multimodal therapy is applied, the outcomes of treatment are still poor, with overall survival and event-free survival of approximately 40% and 30% at 3-years, respectively. The short and long-term side effects of therapy are tremendous. HR NBL carries a high mortality rate accounting for nearly 15% of pediatric cancer deaths. However, most mortalities are attributed to the high frequency of disease relapse (50%) and disease reactiveness to therapy (20%). Newer treatment strategies are therefore urgently needed. Recent discoveries in the field of biology and molecular genetics of NBL have led to the identification of several targets that can improve the treatment results. In this review, we discuss the different aspects of the epidemiology, biology, clinical presentations, diagnosis, and treatment of HR NBL, in addition to the recent developments in the management of the disease.

miR-21 Targets Long Noncoding RNA PCAT29 to Promote Cell Proliferation in Neuroblastoma

Long noncoding RNA (lncRNA) PCAT29 has been characterized as a tumor suppressor in several types of cancer, although its involvement in neuroblastoma (NB) is unknown. In this study, we analyzed the role of PCAT29 in NB. In paired NB and nontumor tissues from 56 patients with NB, microRNA (miR)-21 and PCAT29 expression was determined with reverse transcription quantitative PCR. Correlation between miR-21 and PCAT29 was evaluated with linear regression. The interaction between miR-21 and PCAT29 was predicted by the IntaRNA 2.0 program. In NB cells, miR-21 and PCAT29 were overexpressed to explore their relationship. In NB cell proliferation, the roles of miR-21 and PCAT29 were analyzed with propidium iodide staining and Ki67 staining assays. The results showed that PCAT29 was downregulated and miR-21 was upregulated in NB. MiR-21 was inversely correlated with PCAT29. RNA-RNA interaction prediction revealed that miR-21 might target PCAT29. MiR-21 overexpression reduced PCAT29 expression and increased NB cell proliferation, whereas PCAT29 overexpression inhibited NB cell proliferation. PCAT29 overexpression promoted NB cell apoptosis, while miR-21 overexpression inhibited NB cell apoptosis and attenuated PCAT29 overexpression-mediated NB cell apoptosis. In conclusion, MiR-21 may target PCAT29 to promote cell apoptosis in NB.

Spatial and temporal intratumour heterogeneity has potential consequences for single biopsy-based neuroblastoma treatment decisions

Intratumour heterogeneity is a major cause of treatment failure in cancer. We present in-depth analyses combining transcriptomic and genomic profiling with ultra-deep targeted sequencing of multiregional biopsies in 10 patients with neuroblastoma, a devastating childhood tumour. We observe high spatial and temporal heterogeneity in somatic mutations and somatic copy-number alterations which are reflected on the transcriptomic level. Mutations in some druggable target genes including ALK and FGFR1 are heterogeneous at diagnosis and/or relapse, raising the issue whether current target prioritization and molecular risk stratification procedures in single biopsies are sufficiently reliable for therapy decisions. The genetic heterogeneity in gene mutations and chromosome aberrations observed in deep analyses from patient courses suggest clonal evolution before treatment and under treatment pressure, and support early emergence of metastatic clones and ongoing chromosomal instability during disease evolution. We report continuous clonal evolution on mutational and copy number levels in neuroblastoma, and detail its implications for therapy selection, risk stratification and therapy resistance.

Neuroblastoma-Telomere maintenance, deregulated signaling transduction and beyond

The childhood malignancy neuroblastoma belongs to the group of embryonal tumors and originates from progenitor cells of the sympathoadrenal lineage. Treatment options for children with high-risk and relapsed disease are still very limited. In recent years, an ever-growing molecular diversity was identified using (epi)-genetic profiling of neuroblastoma tumors, indicating that molecularly targeted therapies could be a promising therapeutic option. In this review article, we summarize the various molecular subtypes and genetic events associated with neuroblastoma and describe recent advances in targeted therapies. We lay a strong emphasis on the importance of telomere maintenance mechanisms for understanding tumor progression and risk classification of neuroblastoma.

Genetic Alterations and Resectability Predict Outcome in Patients with Neuroblastoma Assigned to High-Risk Solely by MYCN Amplification

Simple Summary

Currently, patients with high-risk neuroblastoma are uniformly treated with maximum therapy. This study investigated a high-risk subgroup characterized by the presence of the amplified MYCN oncogene in the tumor regardless of the stage. In contrast to the corresponding high-risk subgroup consisting of patients with metastases and age at diagnosis over 18 months, the investigated subgroup had generally a superior survival chance. However, the detection of mutations of specific genes in the tumor tissue (RAS and p53 pathway including ALK) had a strong, negative impact. These genes should be therefore also investigated in the future. Complete surgical removal of the primary tumor proved to be beneficial for high-risk neuroblastoma patients assigned to the high-risk category solely by MYCN amplification.

Abstract

Background: To identify variables predicting outcome in neuroblastoma patients assigned to the high-risk group solely by the presence of MYCN oncogene amplification (MNA). Methods: Clinical characteristics, genomic information, and outcome of 190 patients solely assigned to high-risk neuroblastoma by MNA were analyzed and compared to 205 patients with stage 4 neuroblastoma aged ≥18 months with MNA (control group). Results: Event-free survival (EFS) and overall survival (OS) at 10 years were 47% (95%-CI 39–54%) and 56% (95%-CI 49–63%), respectively, which was significantly better than EFS and OS of the control group (EFS 25%, 95%-CI 18–31%, p < 0.001; OS 32% 95%-CI 25–39%, p < 0.001). The presence of RAS-/p53-pathway gene alterations was associated with impaired 10-year EFS and OS (19% vs. 55%, and 19% vs. 67%, respectively; both p < 0.001). In time-dependent multivariable analyses, alterations of RAS-/p53-pathway genes and the extent of the best primary tumor resection were the only independent prognostic variables for OS (p < 0.001 and p = 0.011, respectively). Conclusions: Neuroblastoma patients attributed to high risk solely by MYCN amplification have generally a more favorable outcome. Mutations of genes of the RAS and/or p53 pathways and incomplete resection are the main risk factors predicting poor outcome.

Clinical and molecular characterization of patients with stage 4(M) neuroblastoma aged less than 18 months without MYCN amplification

INTRODUCTION

The survival of children with stage 4(M) neuroblastoma without MYCN amplification and below the age of 18 months is considered better than the still dismal outcome of older high-risk neuroblastoma patients. This study analyzes the impact of clinical and molecular characteristics on the long-term outcome.

PATIENTS AND METHODS

Clinical presentation, survival, and recurrence patterns of patients enrolled onto trials NB90, NB97, and NB2004 were retrospectively analyzed. Gene expression signatures based on RNA microarrays (TH10) were investigated if tumor material was available.

RESULTS

Between 1990 and 2015, 177 patients with stage 4(M) MYCN nonamplified neuroblastoma aged less than 18 months at diagnosis were eligible. After a median follow-up of 9.7 years (IQR 5.0, 13.4), the proportions of 10-year event-free survival (EFS) and overall survival (OS) were 73% (95% confidence interval [CI] 67-79%) and 86% (95% CI 80-92%), respectively. Of the 27 neuroblastoma recurrences, 44% occurred in more than one site. Four additional patients presented histologically mature ganglioneuroma at recurrence. Six patients developed a secondary malignancy. The secondary 5-year EFS and OS of the 27 patients with neuroblastoma recurrence were 44% and 59%, respectively. TH10 gene expression signature was not prognostically predictive in the investigated subcohort.

CONCLUSION

The outcome of patients with stage 4(M) neuroblastoma aged less than 18 months is favorable when treated with high-risk or otherwise intensive therapy. The development of secondary malignancies and the potential of maturation to ganglioneuroma call for a controlled stepwise reduction of treatment intensity.

Prognostic Value of c-MYC Expression in Patients with Peripheral Neuroblastic Tumors

Objective

Neuroblastic tumors are the most common solid tumors in children. The aim of this study was to explore the prognostic value of immunostaining for cellular-myelocytomatosis viral oncogene (c-MYC) expression in patients with peripheral neuroblastic tumors (NTs).

Methods

A retrospective study was conducted to compare the expression of c-MYC detected by immunohistochemistry and v-myc avian myelocytomatosis viral oncogene neuroblastoma derived homolog (MYCN) by fluorescence in situ hybridization among 177 cases of NTs and determine the associations of c-MYC and MYCN with the clinical stages, morphological types, and survival rates of NTs.

Results

The cases positive for c-MYC were mainly the favorable histology type in stage 3 or 4 with a poor NT prognosis, but no morphological changes related to the poor prognosis were observed in their samples under a microscope. The cases with positive c-MYC expression did not overlap those with MYCN amplification.

Conclusion

Positive c-MYC expression portends a poor prognosis in patients with NTs.

Chromosome 10 abnormality predicts prognosis of neuroblastoma patients with bone marrow metastasis

BACKGROUND

Neuroblastoma (NB) is the most common extracranial solid tumor in children. It is known for high heterogeneity and concealed onset. In recent years, the mechanism of its occurrence and development has been gradually revealed. The purpose of this study is to summarize the clinical characteristics of children with NB and abnormal chromosome 10, and to investigate the relationship between the number and structure of chromosome 10 abnormalities and NB prognosis.

METHODS

Chromosome G-banding was used at the time of diagnosis to evaluate the genetics of chromosomes in patients with NB and track their clinical characteristics and prognosis. All participants were diagnosed with NB in the Medical Oncology Department of the Beijing Children's Hospital from May 2015 to December 2018 and were followed up with for at least 1 year.

RESULTS

Of all 150 patients with bone marrow metastases, 42 were clearly diagnosed with chromosomal abnormalities. Thirteen patients showed abnormalities in chromosome 10, and chromosome 10 was the most commonly missing chromosome. These 13 patients had higher LDH and lower OS and EFS than children with chromosomal abnormalities who did not have an abnormality in chromosome 10. Eight patients had both MYCN amplification and 1p36 deletion. Two patients had optic nerve damage and no vision, and one patient had left supraorbital metastases 5 months after treatment.

CONCLUSIONS

The results indicated that chromosome 10 might be a new prognostic marker for NB. MYCN amplification and 1p36 deletion may be related to chromosome 10 abnormalities in NB. Additionally, NB patients with abnormal chromosome 10 were prone to orbital metastases.

Inhibition of glycolysis and mitochondrial respiration promotes radiosensitisation of neuroblastoma and glioma cells

BACKGROUND

Neuroblastoma accounts for 7% of paediatric malignancies but is responsible for 15% of all childhood cancer deaths. Despite rigorous treatment involving chemotherapy, surgery, radiotherapy and immunotherapy, the 5-year overall survival rate of high-risk disease remains < 40%, highlighting the need for improved therapy. Since neuroblastoma cells exhibit aberrant metabolism, we determined whether their sensitivity to radiotherapy could be enhanced by drugs affecting cancer cell metabolism.

METHODS

Using a panel of neuroblastoma and glioma cells, we determined the radiosensitising effects of inhibitors of glycolysis (2-DG) and mitochondrial function (metformin). Mechanisms underlying radiosensitisation were determined by metabolomic and bioenergetic profiling, flow cytometry and live cell imaging and by evaluating different treatment schedules.

RESULTS

The radiosensitising effects of 2-DG were greatly enhanced by combination with the antidiabetic biguanide, metformin. Metabolomic analysis and cellular bioenergetic profiling revealed this combination to elicit severe disruption of key glycolytic and mitochondrial metabolites, causing significant reductions in ATP generation and enhancing radiosensitivity. Combination treatment induced G2/M arrest that persisted for at least 24 h post-irradiation, promoting apoptotic cell death in a large proportion of cells.

CONCLUSION

Our findings demonstrate that the radiosensitising effect of 2-DG was significantly enhanced by its combination with metformin. This clearly demonstrates that dual metabolic targeting has potential to improve clinical outcomes in children with high-risk neuroblastoma by overcoming radioresistance.

Age at diagnosis as a prognostic factor in South African children with neuroblastoma

PURPOSE

Low- and middle-income countries (LMICs) reported a higher median age at diagnosis of neuroblastoma (NB) compared to high-income countries. The aim was to determine if the optimal age at diagnosis, which maximizes the difference in overall survival between younger versus older patients in the South African population was similar to the internationally validated 18 months age cut-point.

METHODS

Four hundred sixty NB patients diagnosed between 2000 and 2016 were included. Receiver operating characteristic (ROC) curves were used to predict potential age cut-point values for overall survival in all risk group classifications. Risk ratios, sensitivity, specificity, and positive and negative predictive values at the specific cut-points were estimated with 95% confidence intervals, and time to mortality by age at the specific cut-points was shown with Kaplan-Meier curves and compared using log-rank tests.

RESULTS

The median age at diagnosis for the total cohort was 31.9 months (range 0.2-204.7). For high-risk (HR), intermediate-risk, low-risk, and very low-risk patients, the median age at diagnosis was, respectively, 36 months (range 0.4-204.7), 16.8 months (range 0.7-145.1), 14.2 months (range 2.0-143.5), and 8.7 months (range 0.2-75.6). The ROC curves for the total NB cohort (area under the curve [AUC] 0.696; P < .001) and HR (AUC 0.682; P < .001) were analyzed further. The optimal cut-point value for the total cohort was at 19.1 months (sensitivity 59%; specificity 78%). The HR cohort had potential cut-point values identified at 18.4 months age at diagnosis (sensitivity 45%; specificity 87%) and 31.1 months (sensitivity 67%; specificity 62%). The 19.1 months cut-point value in the total cohort and the 18.4 months cut-point value in HR were as useful in predicting overall survival as 18 months age at diagnosis.

CONCLUSION

The 18 months cut-point value appears to be the appropriate age for prognostic determination, despite the higher median age at diagnosis in South Africa.

The reliability of bone marrow cytology as response criterion in metastatic neuroblastoma

BACKGROUND

The quantitative assessment of neuroblastoma cell content in bone marrow aspirates for response evaluation has been introduced recently. Data on the concordance of interobserver reports are lacking so far.

METHODS

Investigators of seven European countries representing national reference or large oncological centers convened in 2016. They agreed to quantitatively assess routine bone marrow smears of the participating institutions and to discuss the discrepant results in joint meetings.

RESULTS

From 2017 through 2019, three cytology rounds with 24, 28, and 28 bone marrow samples were run evaluating the representativity of the smears (yes/[restricted]/no) and the presence of tumor cells (yes/no and %). The comparison of the reports using κ (Fleiss) and α (Krippendorff) statistics demonstrated no robust reliabilities. The agreement on the representativity was moderate to poor, on the presence of tumor cells moderate to good, and on the percentage of tumor cells slight to moderate. Though the value of cytology is unquestioned to detect even tiny metastatic cells in bone marrow, the investigators unanimously agreed that a reliable quantification of the tumor cell content in bone marrow smears is unrealistic. For the key issue of representativity, a new practical definition was developed.

CONCLUSION

For any work with bone marrow aspirates, the representativity of the material is of paramount importance. A practical definition is proposed. A reliable quantitative cytological assessment of tumor cell content in bone marrow aspirates is not feasible in metastatic neuroblastoma. Therefore, its use as response criterion should be reconsidered.

Pulmonary Metastasis of Low-risk Perinatal Neuroblastoma After Resection: Implications for Surveillance

In the wake of the Children's Oncology Group (COG) ANBL00P2 trial and the ongoing ANBL1232 trial, an increasing number of children with neonatal neuroblastoma are being managed nonoperatively. We report the case of a patient with low-risk, non-MYCN amplified, neuroblastoma that was diagnosed and resected in the neonatal period but subsequently developed pulmonary metastases by the age of 7 months. Though rare, the possibility of low-risk disease metastasizing during surveillance should be recognized and may not be identified by current protocols.

The Potential of Mesenchymal Stromal Cells in Neuroblastoma Therapy for Delivery of Anti-Cancer Agents and Hematopoietic Recovery

Neuroblastoma is one of the most common pediatric cancers and a major cause of cancer-related death in infancy. Conventional therapies including high-dose chemotherapy, stem cell transplantation, and immunotherapy approach a limit in the treatment of high-risk neuroblastoma and prevention of relapse. In the last two decades, research unraveled a potential use of mesenchymal stromal cells in tumor therapy, as tumor-selective delivery vehicles for therapeutic compounds and oncolytic viruses and by means of supporting hematopoietic stem cell transplantation. Based on pre-clinical and clinical advances in neuroblastoma and other malignancies, we assess both the strong potential and the associated risks of using mesenchymal stromal cells in the therapy for neuroblastoma. Furthermore, we examine feasibility and safety aspects and discuss future directions for harnessing the advantageous properties of mesenchymal stromal cells for the advancement of therapy success.

[Präklinische Untersuchungen von Wechselwirkungen zwischen Mistel und Radio- oder Chemotherapie auf pädiatrische Tumorzellen]

Hintergrund: Mistelanwendungen werden als komplementäre Therapien häufig in der pädiatrischen Onkologie zusammen mit einer Radio- oder Chemotherapie verabreicht. Wechselwirkungen bei simultaner Applikation sind gerade in der Pädiatrie von großer Bedeutung, sie sind allerdings nach wie vor unzureichend untersucht. Material und Methoden: Zytotoxische Effekte des Mistelextraktes abnobaVISCUM Fraxini (aVF) auf LAN-1 Neuroblastomzellen und deren Etoposid- bzw. Cisplatin-resistente Subzelllinien wurden mittels Viabilitätstest untersucht, sowie mögliche Synergieeffekte zwischen aVF und den Chemotherapeutika durch die Softwareprodukte Combenefit und CompuSyn analysiert. Effekte einer Kombinationstherapie aus aVF und Bestrahlung auf SH-SY5Y Zellen wurden mittels Koloniebildungstest untersucht und Auswirkungen auf die Reparatureffizienz strahleninduzierter Doppelstrangbrüche mit Hilfe durchflusszytometrischer Quantifizierungen von γ-H2AX-Foci nach PI/FITC Doppelfärbung analysiert. Ergebnisse: Die Chemotherapie-resistenten LAN-1 Subzelllinien erwiesen sich als resistenter gegenüber der Mistelbehandlung als die Ursprungszelllinie. Auf Basis vier verschiedener Referenz-modelle konnten vor allem synergistisch/additive Effekte zwischen aVF und den Zytostatika Etoposid und Cisplatin berechnet werden. Die Kombination aus Mistelbehandlung und Bestrahlung führte zu einer Verringerung der Koloniebildung und zu einer Verzögerung der Reparaturgeschwindigkeit von strahleninduzierten Doppelstrangbrüchen. Schlussfolgerung: Die präklinischen Daten könnten darauf hinweisen, dass die Verwendung des Mistelextraktes, aVF, eine unterstützende Wirkung auf Radio- und Chemotherapien hat.

BACKGROUND

Mistletoe therapies belong to the field of complementary medicines and are often administered simultaneously or successive to conventional radio- or chemotherapy. Drug-herb interactions are of great significance, especially in pediatrics, but are still insufficiently investigated.

MATERIAL AND METHODS

Cytotoxic effects of the mistletoe extract, abnobaVISCUM Fraxini (aVF), on LAN-1 neuroblastoma cell line and their chemotherapy-resistant (cisplatin; etoposide) subclones were investigated by cell viability assays. Potential synergistic or antagonistic effects of the co-treatment of aVF and cisplatin or etoposide, respectively, were analyzed by Combenefit and CompuSyn software. Combinational effects of mistletoe and irradiation were assessed by colony formation assays and repair efficiency of irradiation-induced double strand breaks was investigated by flow cytometric analyses of γ-H2AX foci after PI/FITC double staining.

RESULTS

Chemotherapy-resistant subclones were more resistant to mistletoe therapy than the parental cells. Based on four different reference models, primarily synergistic/additive effects between aVF and the cytostatic drugs could be calculated. Simultaneous application of mistletoe extract and irradiation led to a delay of irradiation-induced double strand break repair in neuroblastoma cells and a decreased colony formation compared to irradiation monotherapy.

CONCLUSION

The preclinical data may indicate that the use of aVF has a supportive effect on radio- and chemotherapies.

Mesenchymal Stromal Cells in Neuroblastoma: Exploring Crosstalk and Therapeutic Implications

Neuroblastoma (NB) is the second most common solid cancer in childhood, accounting for 15% of cancer-related deaths in children. In high-risk NB patients, the majority suffers from metastasis. Despite intensive multimodal treatment, long-term survival remains <40%. The bone marrow (BM) is among the most common sites of distant metastasis in patients with high-risk NB. In this environment, small populations of tumor cells can persist after treatment (minimal residual disease) and induce relapse. Therapy resistance of these residual tumor cells in BM remains a major obstacle for the cure of NB. A detailed understanding of the microenvironment and its role in tumor progression is of utmost importance for improving the treatment efficiency of NB. In BM, mesenchymal stromal cells (MSCs) constitute an important part of the microenvironment, where they support hematopoiesis and modulate immune responses. Their role in tumor progression is not completely understood, especially for NB. Although MSCs have been found to promote epithelial-mesenchymal transition, tumor growth, and metastasis and to induce chemoresistance, some reports point toward a tumor-suppressive effect of MSCs. In this review, we aim to compile current knowledge about the role of MSCs in NB development and progression. We evaluate arguments that depict tumor-supportive versus -suppressive properties of MSCs in the context of NB and give an overview of factors involved in MSC-NB crosstalk. A focus lies on the BM as a metastatic niche, since that is the predominant site for NB metastasis and relapse. Finally, we will present opportunities and challenges for therapeutic targeting of MSCs in the BM microenvironment.

Inhibiting phosphoglycerate dehydrogenase counteracts chemotherapeutic efficacy against MYCN-amplified neuroblastoma

Here we sought metabolic alterations specifically associated with MYCN amplification as nodes to indirectly target the MYCN oncogene. Liquid chromatography-mass spectrometry-based proteomics identified seven proteins consistently correlated with MYCN in proteomes from 49 neuroblastoma biopsies and 13 cell lines. Among these was phosphoglycerate dehydrogenase (PHGDH), the rate-limiting enzyme in de novo serine synthesis. MYCN associated with two regions in the PHGDH promoter, supporting transcriptional PHGDH regulation by MYCN. Pulsed stable isotope-resolved metabolomics utilizing ¹³ C-glucose labeling demonstrated higher de novo serine synthesis in MYCN-amplified cells compared to cells with diploid MYCN. An independence of MYCN-amplified cells from exogenous serine and glycine was demonstrated by serine and glycine starvation, which attenuated nucleotide pools and proliferation only in cells with diploid MYCN but did not diminish these endpoints in MYCN-amplified cells. Proliferation was attenuated in MYCN-amplified cells by CRISPR/Cas9-mediated PHGDH knockout or treatment with PHGDH small molecule inhibitors without affecting cell viability. PHGDH inhibitors administered as single-agent therapy to NOG mice harboring patient-derived MYCN-amplified neuroblastoma xenografts slowed tumor growth. However, combining a PHGDH inhibitor with the standard-of-care chemotherapy drug, cisplatin, revealed antagonism of chemotherapy efficacy in vivo. Emergence of chemotherapy resistance was confirmed in the genetic PHGDH knockout model in vitro. Altogether, PHGDH knockout or inhibition by small molecules consistently slows proliferation, but stops short of killing the cells, which then establish resistance to classical chemotherapy. Although PHGDH inhibition with small molecules has produced encouraging results in other preclinical cancer models, this approach has limited attractiveness for patients with neuroblastoma.

18F-meta-fluorobenzylguanidine (18F-mFBG) to monitor changes in norepinephrine transporter expression in response to therapeutic intervention in neuroblastoma models

Targeted radiotherapy with 131I-mIBG, a substrate of the human norepinephrine transporter (NET-1), shows promising responses in heavily pre-treated neuroblastoma (NB) patients. Combinatorial approaches that enhance 131I-mIBG tumour uptake are of substantial clinical interest but biomarkers of response are needed. Here, we investigate the potential of 18F-mFBG, a positron emission tomography (PET) analogue of the 123I-mIBG radiotracer, to quantify NET-1 expression levels in mouse models of NB following treatment with AZD2014, a dual mTOR inhibitor. The response to AZD2014 treatment was evaluated in MYCN amplified NB cell lines (Kelly and SK-N-BE(2)C) by Western blot (WB) and immunohistochemistry. PET quantification of 18F-mFBG uptake post-treatment in vivo was performed, and data correlated with NET-1 protein levels measured ex vivo. Following 72 h AZD2014 treatment, in vitro WB analysis indicated decreased mTOR signalling and enhanced NET-1 expression in both cell lines, and 18F-mFBG revealed a concentration-dependent increase in NET-1 function. AZD2014 treatment failed however to inhibit mTOR signalling in vivo and did not significantly modulate intratumoural NET-1 activity. Image analysis of 18F-mFBG PET data showed correlation to tumour NET-1 protein expression, while further studies are needed to elucidate whether NET-1 upregulation induced by blocking mTOR might be a useful adjunct to 131I-mIBG therapy.

Curcumin's Beneficial Effects on Neuroblastoma: Mechanisms, Challenges, and Potential Solutions

Curcumin, a natural polyphenolic compound derived from the South Asian turmeric plant (Curcuma longa), has well-characterized antioxidant, anti-inflammatory, anti-protein-aggregate, and anticancer properties. Neuroblastoma (NB) is a cancer of the nervous system that arises primarily in pediatric patients. In order to reduce the multiple disadvantages and side effects of conventional oncologic modalities and to potentially overcome cancer drug resistance, natural substances such as curcumin are examined as complementary and supportive therapies against NB. In NB cell lines, curcumin by itself promotes apoptosis and cell cycle arrest through the suppression of serine–threonine kinase Akt and nuclear factor kappa of activated B-cells (NF-κB) signaling, induction of mitochondrial dysfunction, and upregulation of p53 and caspase signaling. While curcumin demonstrates anti-NB efficacy in vitro, cross-validation between NB cell types is currently lacking for many of its specific mechanistic activities. Furthermore, curcumin’s low bioavailability by oral administration, poor absorption, and relative insolubility in water pose challenges to its clinical introduction. Numerous curcumin formulations, including nanoparticles, nanocarriers, and microemulsions, have been developed, with these having some success in the treatment of NB. In the future, standardization and further basic and preclinical trials will be required to ensure the safety of curcumin formulations. While the administration of curcumin is clinically safe even at high doses, clinical trials are necessary to substantiate the practical efficacy of curcumin in the prevention and treatment of NB.

Amino Acids Regulate Cisplatin Insensitivity in Neuroblastoma

Simple Summary

Neuroblastomas mostly show poor response to the Cisplatin therapy. Amino acids serve as building blocks for proteins, which are acquired either through diet or protein breakdown. Our study reveals high amino acid pools and dependence of Cisplatin-tolerant neuroblastomas cells on amino acids for their survival, especially, in drug treated conditions. Our study also demonstrates that response of neuroblastomas to Cisplatin can be improved by decreasing cellular amino acid levels either by reducing amino acid supplements or by applying autophagy inhibitor, Hydroxychloroquine. Thus, our findings establish that neuroblastomas can be sensitized to Cisplatin by targeting amino acid metabolism.

Abstract

Neuroblastoma are pediatric, extracranial malignancies showing alarming survival prognosis outcomes due to their resilience to current aggressive treatment regimens, including chemotherapies with cisplatin (CDDP) provided in the first line of therapy regimens. Metabolic deregulation supports tumor cell survival in drug-treated conditions. However, metabolic pathways underlying cisplatin-resistance are least studied in neuroblastoma. Our metabolomics analysis revealed that cisplatin-insensitive cells alter their metabolism; especially, the metabolism of amino acids was upregulated in cisplatin-insensitive cells compared to the cisplatin-sensitive neuroblastoma cell line. A significant increase in amino acid levels in cisplatin-insensitive cells led us to hypothesize that the mechanisms upregulating intracellular amino acid pools facilitate insensitivity in neuroblastoma. We hereby report that amino acid depletion reduces cell survival and cisplatin-insensitivity in neuroblastoma cells. Since cells regulate their amino acids levels through processes, such as autophagy, we evaluated the effects of hydroxychloroquine (HCQ), a terminal autophagy inhibitor, on the survival and amino acid metabolism of cisplatin-insensitive neuroblastoma cells. Our results demonstrate that combining HCQ with CDDP abrogated the amino acid metabolism in cisplatin-insensitive cells and sensitized neuroblastoma cells to sub-lethal doses of cisplatin. Our results suggest that targeting of amino acid replenishing mechanisms could be considered as a potential approach in developing combination therapies for treating neuroblastomas.

Implementation of the plasma MYCN/NAGK ratio to detect MYCN amplification in patients with neuroblastoma

Detection of amplification of the MYCN gene is essential for determining optimal treatment and estimating prognosis of patients with neuroblastoma (NB). DNA FISH with neuroblastoma tissues or patient‐derived bone marrow cells is the standard clinical practice for the detection of MYCN amplification. As tumor cells may often be unavailable, we developed a method to detect MYCN amplification in the plasma of patients with neuroblastoma. Taking single‐copy NAGK DNA as reference, we used real‐time quantitative PCR (qPCR) to determine the MYCN/NAGK ratio in the plasma of 115 patients diagnosed with NB. An increased MYCN/NAGK ratio in the plasma was consistent with MYCN amplification as assessed by DNA FISH. The AUC for a MYCN/NAGK ratio equal to 6.965 was 0.943, with 86% sensitivity and 100% specificity. Beyond the threshold of 6.965, the MYCN/NAGK ratio correlated with a heavier tumor burden. Event‐free and overall survival of two years were significantly shortened in stage 4 patients with a MYCN/NAGK ratio higher than 6.965. Plasma MYCN/NAGK ratios increased in patients with progressive disease and relapse. Thus, we conclude that the determination of the plasma MYCN/NAGK ratio by qPCR is a noninvasive and reproducible method to measure MYCN amplification in patients with NB.