Socioeconomic status and global variations in the incidence of neuroblastoma: call for support of population-based cancer registries in low-middle-income countries

Exploration of genetic ancestry and socioeconomic status in the incidence of neuroblastoma: An ecological study

Although global differences in the incidence of neuroblastoma have been examined, the underlying mechanism has yet to be elucidated. Previous studies have suggested genetic ancestry and human development index (HDI) as contributing factors, but few studies have been conducted at the international level. Here, we aimed to examine whether the frequency of common genomic variation associated with neuroblastoma can affect its risk at the ecological level with consideration of the HDI. Minor allele frequencies (MAFs) for 22 single-nucleotide polymorphisms (SNPs) were abstracted from the Geography of Genetic Variants Browser. The number of incident neuroblastomas for each population was obtained from the Cancer Incidence in Five Continents series. Further, population pseudo-polygenic risk scores (pp-PRSs) were calculated as a sum of MAFs at the population level, each of which was weighted by effect sizes from prior studies. Negative binomial regression was used to estimate the incidence rate ratios (IRRs) and the 95% confidence intervals (CIs) to examine whether differences in MAFs across the population influence the risk of neuroblastoma, with and without adjustment for HDI and whether pp-PRSs can be a predictor of the risk of neuroblastoma. Overall, our results indicated that the neuroblastoma risk associated with variation in SNP frequency could not be differentiated from that of HDI at the ecological level. Additionally, pp-PRSs were not significantly associated with the risk of neuroblastoma (IRR: 0.99, 95% CI: 0.62-1.60). Further study using individual-level data is warranted to minimize the bias related to the use of population-level data in this study.

Socioeconomic status and retinoblastoma survival: Experience of a tertiary cancer center in Brazil

BACKGROUND

Little is known about socioeconomic status (SES) and its effects in childhood cancer survival. This study aims to discuss the association between SES and survival of patients with retinoblastoma (RB) from a tertiary treatment center.

PROCEDURE

A retrospective cohort study was conducted, including all patients with RB referred to the Brazilian National Institute of Cancer in Rio de Janeiro (January 2000-December 2016).

RESULTS

Data from 160 patients were analyzed with mean age at diagnosis of 22.85 months (SD ± 14.29). Eighty-three patients (51.9%) had an interval to diagnosis equal to or longer than six months, and 13 children (8.1%) abandoned treatment. Five-year overall survival rate for all patients was 78.8% (95% CI, 72.4%-85.9%). In a multivariate model, patients whose fathers had more than nine years of study had a lower death risk. Patients from families having more than one child under five years had a 213% higher risk of death compared with those living with no other small child. Treatment abandonment also had a profound effect on death risk.

CONCLUSION

Childhood cancer is notably important considering the potential years of life lost. RB has even more important elements, as the possibility of vision loss in cases with delayed diagnosis. Family characteristics seem to be highly related to RB survival, especially in low- and middle-income countries, where inequalities are still a public health issue. Strategies to improve survival should focus not only on large-scale settings such as improving national healthcare systems but also on more personalized actions that might help to mitigate disparities.

Management of neuroblastoma in limited-resource settings

BACKGROUND

Neuroblastoma (NB) is a heterogeneous disease with variable outcomes among countries. Little is known about NB in low- and middle-income countries (LMICs).

AIM

The aim of this review was to evaluate regional management protocols and challenges in treating NB in paediatric oncology units in LMICs compared to high-income countries (HICs).

METHODS

PubMed, Global Health, Embase, SciELO, African Index Medicus and Google Scholar were searched for publications with keywords pertaining to NB, LMICs and outcomes. Only English language manuscripts and abstracts were included. A descriptive review was done, and tables illustrating the findings were constructed.

RESULTS

Limited information beyond single-institution experiences regarding NB outcomes in LMICs was available. The disease characteristics varied among countries for the following variables: sex, age at presentation, MYCN amplification, stage and outcome. LMICs were found to be burdened with a higher percentage of stage 4 and high-risk NB compared to HICs. Implementation of evidence-based treatment protocols was still a barrier to care. Many socioeconomic variables also influenced the diagnosis, management and follow-up of patients with NB.

CONCLUSION

Patients presented at a later age with more advanced disease in LMICs. Management was limited by the lack of resources and genetic studies for improved NB classification. Further research is needed to develop modified diagnostic and treatment protocols for LMICs in the face of limited resources.

Correlation Between MYCN Gene Status and MYCN Protein Expression in Neuroblastoma: A Pilot Study To Propose the Use of MYCN Immunohistochemistry in Limited-Resource Areas

PURPOSE

The most significant adverse risk factor for neuroblastoma (NB) is MYCN gene amplification, which strongly associates with high-risk disease. Fluorescent in situ hybridization (FISH) is considered the best method to evaluate MYCN gene status. However, it requires a laboratory that can perform highly complex testing, specialized personnel, and costly reagents. Herein, we aimed to investigate the feasibility of using immunohistochemistry (IHC) to detect MYCN protein expression in lieu of FISH, a strategy potentially useful in areas with limited resources.

METHODS

A pilot cohort of 78 patients with NB, including 34 of Middle Eastern descent (MED) who had a higher prevalence of MYCN gene amplification (44.11%) and 44 of North American descent (NAD), nine (20.45%) of whom had MYCN amplification, was evaluated with IHC for MYCN protein. Correlations of FISH results and protein expression are presented.

RESULTS

A positive correlation between MYCN gene amplification and protein expression by IHC was seen in 22 (91.66%) of the 24 MYCN-amplified NB cases—14 (93.33%) of 15 patients of MED and eight (88.88%) of nine patients of NAD. Agreement between negative FISH and negative IHC results was noted in 18 (94.73%) patients of MED and 34 (97.14%) patients of NAD. Two cases had weak protein expression but no gene amplification (MED: n = 1; 5.0%; NAD: n = 1; 2.9%).

CONCLUSION

An excellent overall correlation between MYCN gene status by FISH and MYCN protein expression by IHC was confirmed. MYCN IHC in NB with reflexing to FISH in equivocal cases is potentially useful in a limited-resource setting. Evaluation of effectiveness using a larger cohort and optimization to perform MYCN IHC manually is needed.

Effect of dexmedetomidine anesthesia on respiratory function in pediatric patients undergoing retinoblastoma resection

The aim of this study was to investigate the effect of dexmedetomidine (Dex) on the respiratory function during anesthesia induction in pediatric patients undergoing retinoblastoma (RB) resection. A total of 87 pediatric patients who underwent RB resection in Yidu Central Hospital of Weifang were recruited into this study. General anesthesia was first induced for all patients, of which 45 were randomly assigned to the experimental group and received Dex through an intravenous infusion pump to maintain general anesthesia. The remaining 42 patients were assigned to the control group and received saline through an intravenous infusion pump. Respiratory function and hemodynamic indexes at five time-points, i.e., before anesthesia induction (T0), 5 min after injection of anesthetic agents (T1), before intubation (T2), 15 min after intubation (T3), and 30 min after extubation (T4), were recorded and compared. Incidence of perioperative cardiac and respiratory adverse events was counted in both groups, and post-anesthesia resuscitation was evaluated and compared. Compared with T0, the respiratory rate (R) of the experimental group was lower at T1-T4, but there was no statistical difference (P<0.05). Compared with T0, the control group had a higher R at T2, lower R at T3 and T4 (P<0.05), and there was no significant difference in R between T0 and T1 (P>0.05). At the same time-point, compared with the experimental group, the R was higher at T2, and lower at T3 and T4 in the control group (P<0.05), and no significant difference was found at T1. Blood oxygen saturation (SpO₂) of the experimental group was slightly lower than that of T0 at T1-T4 (P>0.05). In the control group, the levels of SpO₂ were significantly lower at T1-T4 than those at T0 (P<0.05). Compared with the experimental group at the same time-point, SpO₂ of the control group at T1-T4 decreased significantly (P<0.05). The heart rate (HR) of the experimental and control groups was lower at T1-T4 than that at T0 (P<0.05). The HR of the experimental group was higher than that of the control group at T1-T4 (P<0.05). Mean arterial pressure (MAP) of the experimental and control groups was lower at T1-T4 than that at T0 (P<0.05). MAP of the control group was higher than that of the experimental group at T2 but lower than that at T0 of the control group. MAP of the control group was lower than that of the experimental group at T1-T4. There was no significant difference in incidence of tachycardia, bradycardia, vomiting, hypoxia and laryngism between the two groups (P>0.05). There was no difference in resuscitation and extubation time between the two groups (P>0.05). Finally, agitation of the control group was more severe than that of the experimental group (P<0.05). Therefore, Dex can improve the respiratory function and hemodynamic stability during anesthesia induction in children with RB resection.

Childhood cancer burden: a review of global estimates

5-year net survival of children and adolescents diagnosed with cancer is approximately 80% in many high-income countries. This estimate is encouraging as it shows the substantial progress that has been made in the diagnosis and treatment of childhood cancer. Unfortunately, scarce data are available for low-income and middle-income countries (LMICs), where nearly 90% of children with cancer reside, suggesting that global survival estimates are substantially worse in these regions. As LMICs are undergoing a rapid epidemiological transition, with a shifting burden from infectious diseases to non-communicable diseases, cancer care for all ages has become a global focus. To improve outcomes for children and adolescents diagnosed with cancer worldwide, an accurate appraisal of the global burden of childhood cancer is a necessary first step. In this Review, we analyse four studies of the global cancer burden that included data for children and adolescents. Each study used various overlapping and non-overlapping statistical approaches and outcome metrics. Moreover, to provide guidance on improving future estimates of the childhood global cancer burden, we propose several recommendations to strengthen data collection and standardise analyses. Ultimately, these data could help stakeholders to develop plans for national and institutional cancer programmes, with the overall aim of helping to reduce the global burden of cancer in children and adolescents.

Novel Combination of Arsenic Trioxide (As2O3) Plus Resveratrol in Inducing Programmed Cell Death of Human Neuroblastoma SK-N-SH Cells

AIM

Arsenic trioxide (As₂O₃), known as pi-shuang and the most toxic compound in traditional Chinese medicine, has been used as an antitumor agent for thousands of years. Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural phenol that has significant anti-bacterial, anti-fungaI and antiaging activities. Our study aimed to examine the combined anticancer effects of As₂O₃ and resveratrol against human neuroblastoma SK-N-SH cells, and elucidate the underlying intracellular signaling.

MATERIALS AND METHODS

SK-N-SH cells were treated with an extremely low-dose (2-4 μM) of As₂O₃ alone or combined with 75 μg/ml resveratrol for further comparisons. Cell viability, apoptotic signaling as well as synergistic cytotoxic effects were estimated using the MTT assay, microscopy observation, flow cytometric analysis for loss of mitochondrial membrane potential (MMP) and reactive oxygen species (ROS), and typical quantitative western blotting analysis. Student's t-test, and one- and two-way analysis of variance (ANOVA) were used for examination of significant differences.

RESULTS

The combined treatment was more effective than single treatment of As₂O₃ or resveratrol alone in suppressing cell viability, which correlated with the elevation of ROS levels. The intracellular mechanisms of cytotoxicity of As₂O₃ plus resveratrol were revealed as ROS accumulation and relative decrease of MMP, leading to activation of caspase-3 and -9, but not of caspase-1, -7 and-8. Combination treatment reduced the expression of B-cell lymphoma 2 (BCL2), BH3 interacting domain death agonist (BID), and BCL-x/L.

CONCLUSION

Combined treatment at extremely low concentration of two agents from natural products, As₂O₃ and resveratrol, has high potential as a cocktail of anticancer drugs for neuroblastoma.

Pediatric Solid Tumors in Resource-Constrained Settings: A Review of Available Evidence on Management, Outcomes, and Barriers to Care

International disparities in outcomes from pediatric solid tumors remain striking. Herein, we review the current literature regarding management, outcomes, and barriers to care for pediatric solid tumors in low- and middle-income countries (LMICs). In sub-Saharan Africa, Wilms Tumor represents the most commonly encountered solid tumor of childhood and has been the primary target of recent efforts to improve outcomes in low-resource settings. Aggressive and treatment-resistant tumor biology may play a role in poor outcomes within certain populations, but socioeconomic barriers remain the principal drivers of preventable mortality. Management protocols that include measures to address socioeconomic barriers have demonstrated early success in reducing abandonment of therapy. Further work is required to improve infrastructure and general pediatric care to address disparities.

Socioeconomic Status and Childhood Cancer Incidence: A Population-Based Multilevel Analysis

The etiology of childhood cancers remains largely unknown, especially regarding environmental and behavioral risk factors. Unpacking the association between socioeconomic status (SES) and incidence may offer insight into such etiology. We tested associations between SES and childhood cancer incidence in a population-based case-cohort study (source cohort: Minnesota birth registry, 1989-2014). Cases, ages 0-14 years, were linked from the Minnesota Cancer Surveillance System to birth records through probabilistic record linkage. Controls were 4:1 frequency matched on birth year (2,947 cases and 11,907 controls). We tested associations of individual-level (maternal education) and neighborhood-level (census tract composite index) SES using logistic mixed models. In crude models, maternal education was positively associated with incidence of acute lymphoblastic leukemia (odds ratio (OR) = 1.10, 95% confidence interval (CI): 1.02, 1.19), central nervous system tumors (OR = 1.12, 95% CI: 1.04, 1.21), and neuroblastoma (OR = 1.15, 95% CI: 1.02, 1.30). Adjustment for established risk factors-including race/ethnicity, maternal age, and birth weight-substantially attenuated these positive associations. Similar patterns were observed for neighborhood-level SES. Conversely, higher maternal education was inversely associated with hepatoblastoma incidence (adjusted OR = 0.70, 95% CI: 0.51, 0.98). Overall, beyond the social patterning of established demographic and pregnancy-related exposures, SES is not strongly associated with childhood cancer incidence.

Persisting inequalities in survival patterns of childhood neuroblastoma in Southern and Eastern Europe and the effect of socio-economic development compared with those of the US

AIM

Neuroblastoma outcomes vary with disease characteristics, healthcare delivery and socio-economic indicators. We assessed survival patterns and prognostic factors for patients with neuroblastoma in 11 Southern and Eastern European (SEE) countries versus those in the US, including-for the first time-the Nationwide Registry for Childhood Hematological Malignancies and Solid Tumours (NARECHEM-ST)/Greece.

METHODS

Overall survival (OS) was calculated in 13 collaborating SEE childhood cancer registries (1829 cases, ∼1990-2016) and Surveillance, Epidemiology, and End Results (SEER), US (3072 cases, 1990-2012); Kaplan-Meier curves were used along with multivariable Cox regression models assessing the effect of age, gender, primary tumour site, histology, Human Development Index (HDI) and place of residence (urban/rural) on survival.

RESULTS

The 5-year OS rates varied widely among the SEE countries (Ukraine: 45%, Poland: 81%) with the overall SEE rate (59%) being significantly lower than in SEER (77%; p < 0.001). In the common registration period within SEE (2000-2008), no temporal trend was noted as opposed to a significant increase in SEER. Age >12 months (hazard ratio [HR]: 2.8-4.7 in subsequent age groups), male gender (HR: 1.1), residence in rural areas (HR: 1.3), living in high (HR: 2.2) or medium (HR: 2.4) HDI countries and specific primary tumour location were associated with worse outcome; conversely, ganglioneuroblastoma subtype (HR: 0.28) was associated with higher survival rate.

CONCLUSIONS

Allowing for the disease profile, children with neuroblastoma in SEE, especially those in rural areas and lower HDI countries, fare worse than patients in the US, mainly during the early years after diagnosis; this may be attributed to presumably modifiable socio-economic and healthcare system performance differentials warranting further research.

An overview of disparities in childhood cancer: Report on the Inaugural Symposium on Childhood Cancer Health Disparities, Houston, Texas, 2016

The Inaugural Symposium on Childhood Cancer Health Disparities was held in Houston, Texas, on November 2, 2016. The symposium was attended by 109 scientists and clinicians from diverse disciplinary backgrounds with interests in pediatric cancer disparities and focused on reviewing our current knowledge of disparities in cancer risk and outcomes for select childhood cancers. Following a full day of topical sessions, everyone participated in a brainstorming session to develop a working strategy for the continued expansion of research in this area. This meeting was designed to serve as a springboard for examination of childhood cancer disparities from a more unified and systematic approach and to enhance awareness of this area of need.

Triptolide Inhibits Proliferation and Migration of Human Neuroblastoma SH-SY5Y Cells by Upregulating MicroRNA-181a

Neuroblastoma is the primary cause of cancer-related death for children 1 to 5 years of age. New therapeutic strategies and medicines are urgently needed. This study aimed to investigate the effects of triptolide (TPL), the major active component purified from Tripterygium wilfordii Hook F, on neuroblastoma SH-SY5Y cell proliferation, migration, and apoptosis, as well as underlying potential mechanisms. We found that TPL inhibited SH-SY5Y cell viability, proliferation, and migration, but induced cell apoptosis. The expression of matrix metalloproteinase-2 (MMP-2) and MMP-9 after TPL treatment in SH-SY5Y cells was decreased. The expression of microRNA-181a (miR-181a) was upregulated after TPL treatment. Moreover, suppression of miR-181a reversed the effects of TPL on SH-SY5Y cell proliferation, apoptosis, and migration. Overexpression of miR-181a enhanced the TPL-induced activation of p38 mitogen-activated protein kinase (p38MAPK) and nuclear factor κ light chain enhancer of activated B cells (NF-κB) pathways. In conclusion, our research verified that TPL inhibited the proliferation and migration of human neuroblastoma SH-SY5Y cells by upregulating the expression of miR-181a.

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

BACKGROUND

A comprehensive clinical long-term survey over the complete spectrum of neuroblatoma disease is lacking in the literature.

OBJECTIVE

Our objective was to describe the incidence, risk profiles, therapies, and outcomes for the total cohort of German patients with neuroblastoma including all clinical stages and risk groups.

METHODS

Epidemiological, clinical, and outcome data of neuroblastoma patients who participated in one of the six consecutive national trials between 1979 and 2015 were analyzed retrospectively.

RESULTS

Of all German neuroblastoma patients known to the national childhood cancer registry, ninety seven percent enrolled in one of the trials. The absolute neuroblastoma rate has increased slightly, whereas the median age at diagnosis has decreased. Except for the screening period (1995-2000), the risk factors lactate dehydrogenase (LDH), ferritin, chromosome 1p, and the MYCN oncogene have remained largely constant, with the exception of an increase in MYCN amplification at stage 4 for those aged ≥18 months between trials NB97 (27%) and NB2004 (35%). The 10-year overall survival increased in patients with stage 1-3 neuroblastoma from 83 to 91%, for stage 4S from 80 to 85%, and for stage 4 aged ≥18 months from 2 to 38%. The fraction of patients in stages 1-3 who never received chemotherapy (neither for frontline nor at recurrence) increased from 35 to 60%. The proportion of macroscopically complete surgical resections of the primary tumor decreased for the total population as well as for patients with stage 4 aged ≥18 months. The impact of chemotherapy response on the outcome was trial dependent. The overall proportion of toxic death during the time of the protocol therapy was 6% for stage 4 patients aged ≥18 months and 2% for low-/intermediate-risk patients. The most frequently reported late sequelae in stage 4 patients aged ≥18 months were renal dysfunctions, hypothyroidism, major hearing impairment, and second malignancies.

CONCLUSION

The body of data for incidences, risk profiles, and survival rates from this survey of more than 37 years provides a useful perspective for future studies on neuroblastoma sub-cohorts.