Socioeconomic status and the incidence of non-central nervous system childhood embryonic tumours in Brazil

Neuroblastoma of the lumbosacral canal in an adult: a case report and literature review

Neuroblastoma (NB) is a leading cause of death in children. It usually occurs in the adrenal gland and rarely in the spinal canal. Here, we report the case of a 48-year-old male patient with abnormal thickening of the cauda equina nerve as revealed by lumbosacral magnetic resonance imaging. The patient's main clinical manifestations were numbness and pain in both lower limbs. The patient underwent surgical treatment; however, intraoperatively, an unclear border was observed between the cauda equina nerve and the tumor; therefore, the tumor was not forcibly excised. The postoperative pathological results were reported as NB. The disease known as NB, which is extremely rare. We believe that a pathological biopsy is extremely vital for diagnosing NB, and aggressive post-operative radio-chemotherapy could potentially prolong the patient's survival time.

Incidence and geographic distribution of retinoblastoma in Ethiopia

INTRODUCTION

Retinoblastoma is the most frequent intraocular malignancy of the eye in children, occurring in early childhood. Based on global estimates, Ethiopia is expected to observe over 200 new retinoblastoma cases per year, however without a cancer registry, this number is difficult to confirm. Therefore, the goal of the study was to determine the incidence and geographic distribution of retinoblastoma in Ethiopia.

METHODS

A retrospective medical chart review of clinically diagnosed new retinoblastoma patients between January 1, 2017 - December 31, 2020, in four public Ethiopian tertiary hospitals was performed. The incidence of retinoblastoma was calculated by a birth-cohort analysis.

RESULTS

There were 221 retinoblastoma patients observed in the study period. The incidence of retinoblastoma was found to be 1 in 52,156 live births. Incidence varied among different regions of Ethiopia.

CONCLUSION

The incidence of retinoblastoma observed in this study is likely an underestimate. It is possible that patients were undercounted because they were seen outside of the 4 main retinoblastoma treatment facilities included in this facility, or they experienced barriers to accessing care. Our study suggests a need for a nationwide retinoblastoma registry and more retinoblastoma treatment centers in the country.

Pediatric renal tumor epidemiology: Global perspectives, progress, and challenges

Pediatric renal tumors account for 3%-11% of childhood cancers, the most common of which is Wilms tumor or nephroblastoma. Epidemiology plays a key role in cancer prevention and control by describing the distribution of cancer and discovering risk factors for cancer. Large pediatric research consortium trials have led to a clearer understanding of pediatric renal tumors, identification of risk factors, and development of more risk-adapted therapies. These therapies have improved event-free and overall survival for children. However, several challenges remain and not all children have benefited from the improved outcomes. In this article, we review the global epidemiology of pediatric renal tumors, including key consortium and global studies. We identify current knowledge gaps and challenges facing both high and low middle-incomes countries.

Pediatric renal tumor epidemiology: Global perspectives, progress, and challenges

Pediatric renal tumors account for 3%-11% of childhood cancers, the most common of which is Wilms tumor or nephroblastoma. Epidemiology plays a key role in cancer prevention and control by describing the distribution of cancer and discovering risk factors for cancer. Large pediatric research consortium trials have led to a clearer understanding of pediatric renal tumors, identification of risk factors, and development of more risk-adapted therapies. These therapies have improved event-free and overall survival for children. However, several challenges remain and not all children have benefited from the improved outcomes. In this article, we review the global epidemiology of pediatric renal tumors, including key consortium and global studies. We identify current knowledge gaps and challenges facing both high and low middle-incomes countries.

Unraveling the Genetic Architecture of Hepatoblastoma Risk: Birth Defects and Increased Burden of Germline Damaging Variants in Gastrointestinal/Renal Cancer Predisposition and DNA Repair Genes

The ultrarare hepatoblastoma (HB) is the most common pediatric liver cancer. HB risk is related to a few rare syndromes, and the molecular bases remain elusive for most cases. We investigated the burden of rare damaging germline variants in 30 Brazilian patients with HB and the presence of additional clinical signs. A high frequency of prematurity (20%) and birth defects (37%), especially craniofacial (17%, including craniosynostosis) and kidney (7%) anomalies, was observed. Putative pathogenic or likely pathogenic monoallelic germline variants mapped to 10 cancer predisposition genes (CPGs: APC, CHEK2, DROSHA, ERCC5, FAH, MSH2, MUTYH, RPS19, TGFBR2 and VHL) were detected in 33% of the patients, only 40% of them with a family history of cancer. These findings showed a predominance of CPGs with a known link to gastrointestinal/colorectal and renal cancer risk. A remarkable feature was an enrichment of rare damaging variants affecting different classes of DNA repair genes, particularly those known as Fanconi anemia genes. Moreover, several potentially deleterious variants mapped to genes impacting liver functions were disclosed. To our knowledge, this is the largest assessment of rare germline variants in HB patients to date, contributing to elucidate the genetic architecture of HB risk.

A Metabonomic View on Wilms Tumor by High-Resolution Magic-Angle Spinning Nuclear Magnetic Resonance Spectroscopy

Pediatric cancer NMR-metabonomics might be a powerful tool to discover modified biochemical pathways in tumor development, improve cancer diagnosis, and, consequently, treatment. Wilms tumor (WT) is the most common kidney tumor in young children whose genetic and epigenetic abnormalities lead to cell metabolism alterations, but, so far, investigation of metabolic pathways in WT is scarce. We aimed to explore the high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) metabonomics of WT and normal kidney (NK) samples. For this study, 14 WT and 7 NK tissue samples were obtained from the same patients and analyzed. One-dimensional and two-dimensional HR-MAS NMR spectra were processed, and the one-dimensional NMR data were analyzed using chemometrics. Chemometrics enabled us to elucidate the most significant differences between the tumor and normal tissues and to discover intrinsic metabolite alterations in WT. The metabolic differences in WT tissues were revealed by a validated PLS-DA applied on HR-MAS T₂-edited ¹H-NMR and were assigned to 16 metabolites, such as lipids, glucose, and branched-chain amino acids (BCAAs), among others. The WT compared to NK samples showed 13 metabolites with increased concentrations and 3 metabolites with decreased concentrations. The relative BCAA concentrations were decreased in the WT while lipids, lactate, and glutamine/glutamate showed increased levels. Sixteen tissue metabolites distinguish the analyzed WT samples and point to altered glycolysis, glutaminolysis, TCA cycle, and lipid and BCAA metabolism in WT. Significant variation in the concentrations of metabolites, such as glutamine/glutamate, lipids, lactate, and BCAAs, was observed in WT and opened up a perspective for their further study and clinical validation.

The Effects of Breastfeeding on Retinoblastoma Development: Results from an International Multicenter Retinoblastoma Survey

The protective effects of breastfeeding on various childhood malignancies have been established but an association has not yet been determined for retinoblastoma (RB). We aimed to further investigate the role of breastfeeding in the severity of nonhereditary RB development, assessing relationship to (1) age at diagnosis, (2) ocular prognosis, measured by International Intraocular RB Classification (IIRC) or Intraocular Classification of RB (ICRB) group and success of eye salvage, and (3) extraocular involvement. Analyses were performed on a global dataset subgroup of 344 RB patients whose legal guardian(s) consented to answer a neonatal questionnaire. Patients with undetermined or mixed feeding history, family history of RB, or sporadic bilateral RB were excluded. There was no statistically significant difference between breastfed and formula-fed groups in (1) age at diagnosis (p = 0.20), (2) ocular prognosis measures of IIRC/ICRB group (p = 0.62) and success of eye salvage (p = 0.16), or (3) extraocular involvement shown by International Retinoblastoma Staging System (IRSS) at presentation (p = 0.74), lymph node involvement (p = 0.20), and distant metastases (p = 0.37). This study suggests that breastfeeding neither impacts the sporadic development nor is associated with a decrease in the severity of nonhereditary RB as measured by age at diagnosis, stage of disease, ocular prognosis, and extraocular spread. A further exploration into the impact of diet on children who develop RB is warranted.

Clinical Presentation of Retinoblastoma in Ethiopia: A Case of Jimma University Medical Center Pediatric Oncology Unit, Southwest Ethiopia

BACKGROUND

Retinoblastoma (RB) is one of the most curable childhood cancers if early detected and treated. Late presentation complicates the management of RB results in dismal treatment outcome. Objective: The aim of this study is to report the clinical presentation pattern of retinoblastoma patients seen at Jimma University Medical center (JUMC).

METHODS

The study was a retrospective review of retinoblastoma cases managed at JUMC between August 2016 and July 2020.

RESULTS

Among pediatric oncology cases registered retinoblastoma, accounting 8.5 % (36/423) of all childhood cancer patients in the study period, 29 (90.6%) of them had unilateral retinoblastoma and 3(9.4%) of them had bilateral retinoblastoma. The average age at presentation for bilateral and unilateral retinoblastoma patients was 17 (range 3-30) months and 37.5 months (range 8-84) respectively. The first symptom observed by the family was leukocoria in 21 (65.6%) of the patients but 24(75%) of the patients presented with advanced stage (proptosis and fungating orbital mass) of the disease. The longest and the shortest lag time of presentation from the first symptom was 17 months and 2 weeks respectively with the mean lag time of 1.4 months in bilateral and 6 months in unilateral cases. Clinically, the majority of the eyes 24/35(68.6%) were extraocular tumors involving orbital tissues at presentation.

CONCLUSION

Most of retinoblastoma patients presented at advanced stage of the disease and presented very late after the family observed the disease. Early detection strategies must be designed by the government and responsible stakeholders in mitigating the effects of late presentation.

The effectiveness of an oral health education and prevention program on the incidence and severity of oral mucositis in pediatric cancer patients: a non-randomized controlled study

PURPOSE

To investigate the effectiveness of an Oral Health Education and Prevention Program (OHEPP) on the incidence and severity of oral mucositis (OM) in pediatric cancer patients. The OHEEP was a ludic strategy for promoting oral health and monitoring the oral health condition.

METHODS

We compared the incidence and severity of OM in patients who attended the OHEPP against those under similar conditions who did not receive educational interventions. Both groups were examined for 6 weeks by calibrated examiners (k > 0.8) using the modified Oral Assessment Guide (OAG). A total of 14 patients aged 2 to 18 years were included in each group and matched for sex, age, tumor type, and treatment modality. The incidence and severity of OM were compared using the chi-squared test (α = 5%), and the relative risk and effectiveness of the OHEPP were calculated with a statistical power of 0.97. Differences in total OAG scores between the groups were determined by the Mann-Whitney test (α = 5%).

RESULTS

There was a higher incidence of OM in patients who did not attend the OHEPP (P = 0.005), and the relative risk of developing OM was significantly lower in OHEPP attendants (RR: 0.73; CI 0.60-0.92). No difference in the occurrence of severe OM was observed. OHEPP reduced the risk of developing OM by 1.4-fold, with an effectiveness of 27%. There was a difference in total OAG scores (P = 0.041).

CONCLUSION

Participation in OHEPP was an effective measure to reduce the incidence of OM in pediatric cancer patients.

Parental Occupation and Risk of Childhood Retinoblastoma in Denmark

OBJECTIVE

Retinoblastoma is the most common primary intraocular tumor affecting children. We examine the role of parental occupational exposures and risk of retinoblastoma among offspring.

METHODS

Our population-based case-control study linked data from four nationwide Danish registries and included all cases of retinoblastoma diagnosed in Danish children (<5 y, n = 144) between 1975 and 2014. We focused on two biologically relevant time periods: 90 days preconception to conception for fathers; conception to birth for mothers. Parents were grouped into major industry headings created from Danish industry codes.

RESULTS

We observed increased risk of all retinoblastoma for children of fathers in the food and drink industry and iron and metal industry. Bilateral disease was associated with paternal work in manufacturing and land transportation.

CONCLUSION

Our results suggest that some occupational exposures may increase the risk of childhood sporadic retinoblastoma.

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.

Challenges on participation in a cooperative group of childhood renal tumors in Brasil

OBJECTIVE

Children with renal tumors included in clinical trials have significantly better outcomes. In Brasil, the enrollment of patients in clinical trials remains challenging. Here we aimed to describe participation accrual in the Brazilian Wilms Tumor Study Group (BWTSG) and to identify barriers to trial registration of children with renal tumors.

METHODS

We determined the numbers of renal tumor diagnoses in 105 hospital-based cancer registries from 2001-2009. We then compared these totals with the numbers of renal tumor cases registered in the BWTSG from the same hospitals during the same time period. We also invited members of the Brazilian Pediatric Oncology Society to complete a 5-point Likert-type scale questionnaire regarding their opinions of the importance of participation in cooperative group trials.

RESULTS

The accrual rate of patient participation per hospital varied from 25% to 76%, and was highest in the South region. The accrual rate of hospital participation also varied according to the region (20-31%) and was highest in the Southeast region. For the questionnaire regarding the importance of participation in cooperative groups, the responses showed an agreement of >75% on 10 of the 13 statements.

CONCLUSION

Our results demonstrated low accrual of participation in a cooperative group trial in Brasil. We identified variations in registration rates according to geographic region and hospital, which may help targeted efforts to increase registration rates. The survey responses demonstrated that colleagues understand the importance of trial participation.

Genes Controlled by DNA Methylation Are Involved in Wilms Tumor Progression

To identify underlying mechanisms involved with metastasis formation in Wilms tumors (WTs), we performed comprehensive DNA methylation and gene expression analyses of matched normal kidney (NK), WT blastemal component, and metastatic tissues (MT) from patients treated under SIOP 2001 protocol. A linear Bayesian framework model identified 497 differentially methylated positions (DMPs) between groups that discriminated NK from WT, but MT samples were divided in two groups. Accordingly, methylation variance grouped NK and three MT samples tightly together and all WT with four MT samples that showed high variability. WT were hypomethylated compared to NK, and MT had a hypermethylated pattern compared to both groups. The methylation patterns were in agreement with methylases and demethylases expression. Methylation data pointed to the existence of two groups of metastases. While hierarchical clustering analysis based on the expression of all 2569 differentially expressed genes (DEGs) discriminated WT and MT from all NK samples, the hierarchical clustering based on the expression of 44 genes with a differentially methylated region (DMR) located in their promoter region revealed two groups: one containing all NKs and three MTs and one containing all WT and four MTs. Methylation changes might be controlling expression of genes associated with WT progression. The 44 genes are candidates to be further explored as a signature for metastasis formation in WT.

CLINICAL AND EPIDEMIOLOGICAL CHARACTERISTICS AND SURVIVAL OUTCOMES OF CHILDREN WITH NEUROBLASTOMA: 21 YEARS OF EXPERIENCE AT THE INSTITUTO DE ONCOLOGIA PEDIÁTRICA, IN SÃO PAULO, BRAZIL

Objective:

To describe the clinical and epidemiological characteristics and survival outcomes of children with neuroblastoma (NB) treated at a pediatric oncology center from 1991 to 2012.

Methods:

A retrospective study with clinical and epidemiological data from 258 patients with neuroblastoma treated at a pediatric oncology center from 1991 to 2012, using medical records.

Results:

The average age of the children at diagnosis was 40.5±46.4 months with a median age of 28.9 months (interquartile range 42.2). The male:female ratio was 1.3:1, and 1% of the patients were asymptomatic. The most frequent manifestations were: fever (25%), abdominal pain (22%), abdominal mass (19%), and bone pain (19%). The mean time from symptom onset to diagnosis was 3.0±4.8 months. The most common location of the tumor was the abdomen (63%). Metastases occurred in the bone marrow (37%) and in the bone (33%). Overall survival (OS) and event-free survival (EFS) in five years were 62 and 52%, respectively. The main cause of death was the progression of the disease (72%).

Conclusions:

The clinical features of children with neuroblastoma are variable and mostly nonspecific, which makes clinical recognition difficult and, in general, too late. In children less than 5 years old, with an abdominal mass and/or bone pain, irritability, and a fever from an unknown cause, neuroblastoma should be considered as a possible diagnosis.

Childhood nephroblastoma in Southern and Eastern Europe and the US: Incidence variations and temporal trends by human development index

BACKGROUND

Despite advances in the management of nephroblastoma (Wilms' tumor, WT), the etiology of the tumor remains obscure. We aimed to compare nephroblastoma incidence rates and time trends among children (0-14 years) in 12 Southern and Eastern European (SEE) countries and the Surveillance, Epidemiology, and End Results Program (SEER), USA, in relation to the human development index (HDI).

METHODS

In total 1776 WT cases were recorded in 13 SEE collaborating registries (circa 1990-2016), whereas data on 2260 cases (1990-2012) were extracted from the SEER database. Age-standardized incidence rates (AIRs) were calculated and correlated with HDI, whereas temporal trends were evaluated using Poisson regression and Joinpoint analyses.

RESULTS

The overall SEE AIR (9.2/106) was marginally higher than that of the SEER (8.3/106), whereas significant differences were noted among the 13 SEE registries which comprised mainly Caucasian populations. A statistically significant temporal increase in incidence was noted only in Belarus. Most cases (∼75%) were diagnosed before the fifth year of life, with rates steadily declining thereafter; median age at diagnosis was similar in SEE countries and SEER. A slight male preponderance in the first year of life (male:female = 1.1) was followed by a female preponderance in the older age groups (male:female = 0.7). Lastly, a statistically significant positive association between higher HDI and increasing nephroblastoma incidence was noted (regression coefficient: +3.25, 95%CI: +1.35, +5.15).

CONCLUSIONS

Variations in incidence and time trends across the examined registries, changing male-to-female patterns with advancement in age, and positive associations with the HDI imply a plausible role for environmental and genetic factors in disease etiology, and these need to be explored further.

Investigation of major genetic alterations in neuroblastoma

Neuroblastoma (NB) is the most common extracranial solid tumor in childhood. This malignancy shows a wide spectrum of clinical outcome and its prognosis is conditioned by manifold biological and genetic factors. We investigated the tumor genetic profile and clinical data of 29 patients with NB by multiplex ligation-dependent probe amplification (MLPA) to assess therapeutic risk. In 18 of these tumors, MYCN status was assessed by fluorescence in situ hybridization (FISH). Copy number variation was also determined for confirming MLPA findings in two 6p loci. We found 2p, 7q and 17q gains, and 1p and 11q losses as the most frequent chromosome alterations in this cohort. FISH confirmed all cases of MYCN amplification detected by MLPA. In view of unexpected 6p imbalance, copy number variation of two 6p loci was assessed for validating MLPA findings. Based on clinical data and genetic profiles, patients were stratified in pretreatment risk groups according to international consensus. MLPA proved to be effective for detecting multiple genetic alterations in all chromosome regions as requested by the International Neuroblastoma Risk Group (INRG) for therapeutic stratification. Moreover, this technique proved to be cost effective, reliable, only requiring standard PCR equipment, and attractive for routine analysis. However, the observed 6p imbalances made PKHD1 and DCDC2 inadequate for control loci. This must be considered when designing commercial MLPA kits for NB. Finally, four patients showed a normal MLPA profile, suggesting that NB might have a more complex genetic pattern than the one assessed by presently available MLPA kits.

Association between long interspersed nuclear element-1 methylation levels and relapse in Wilms tumors

Background

Wilms tumor (WT) is a curable pediatric renal malignancy, but there is a need for new molecular biomarkers to improve relapse risk-directed therapy. Somatic alterations occur at relatively low frequencies whereas epigenetic changes at 11p15 are the most common aberration. We analyzed long interspersed element-1 (LINE-1) methylation levels in the blastemal component of WT and normal kidney samples to explore their prognostic significance.

Results

WT samples presented a hypomethylated pattern at all five CpG sites compared to matched normal kidney samples; therefore, the averaged methylation levels of the five CpG sites were used for further analyses. WT presented a hypomethylation profile (median 65.0%, 47.4–73.2%) compared to normal kidney samples (median 71.8%, 51.5–77.5%; p < 0.0001). No significant associations were found between LINE-1 methylation levels and clinical–pathological characteristics. We observed that LINE-1 methylation levels were lower in tumor samples from patients with relapse (median methylation 60.5%) compared to patients without relapse (median methylation 66.5%; p = 0.0005), and a receiving operating characteristic curve analysis was applied to verify the ability of LINE-1 methylation levels to discriminate WT samples from these patients. Using a cut-off value of 62.71% for LINE-1 methylation levels, the area under the curve was 0.808, with a sensitivity of 76.5% and a specificity of 83.3%. Having identified differences in LINE-1 methylation between WT samples from patients with and without relapse in this cohort, we evaluated other prognostic factors using a logistic regression model. This analysis showed that in risk stratification, LINE-1 methylation level was an independent variable for relapse risk: the lower the methylation levels, the higher the risk of relapse. The logistic regression model indicated a relapse risk increase of 30% per decreased unit of methylation (odds ratio 1.30; 95% confidence interval 1.07–1.57).

Conclusion

Our results reinforce previous data showing a global hypomethylation profile in WT. LINE-1 methylation levels can be suggested as a marker of relapse after chemotherapy treatment in addition to risk classification, helping to guide new treatment approaches.

Electronic supplementary material

The online version of this article (10.1186/s13148-017-0431-6) contains supplementary material, which is available to authorized users.

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

Global variations in the incidence of pediatric cancers have been described; however, the causes of such differences are not known. We investigated the relationship between the incidence of embryonal tumors and human development index on a global scale. Increasing incidence of neuroblastoma correlates significantly with an increasing index of human development, with greater incidence among countries with high socioeconomic development, in apparent contrast to the incidence of retinoblastoma. While more data are needed to corroborate this observation, our findings suggest new avenues for etiological research and serve as a call for support of population-based cancer registries in low-middle-income countries.

DNA methylation landscape of hepatoblastomas reveals arrest at early stages of liver differentiation and cancer-related alterations

Hepatoblastomas are uncommon embryonal liver tumors accounting for approximately 80% of childhood hepatic cancer. We hypothesized that epigenetic changes, including DNA methylation, could be relevant to hepatoblastoma onset. The methylomes of eight matched hepatoblastomas and non-tumoral liver tissues were characterized, and data were validated in an independent group (11 hepatoblastomas). In comparison to differentiated livers, hepatoblastomas exhibited a widespread and non-stochastic pattern of global low-level hypomethylation. The analysis revealed 1,359 differentially methylated CpG sites (DMSs) between hepatoblastomas and control livers, which are associated with 765 genes. Hypomethylation was detected in hepatoblastomas for ~58% of the DMSs with enrichment at intergenic sites, and most of the hypermethylated CpGs were located in CpG islands. Functional analyses revealed enrichment in signaling pathways involved in metabolism, negative regulation of cell differentiation, liver development, cancer, and Wnt signaling pathway. Strikingly, an important overlap was observed between the 1,359 DMSs and the CpG sites reported to exhibit methylation changes through liver development (p<0.0001), with similar patterns of methylation in both hepatoblastomas and fetal livers compared to adult livers. Overall, our results suggest an arrest at early stages of liver cell differentiation, in line with the hypothesis that hepatoblastoma ontogeny involves the disruption of liver development. This genome-wide methylation dysfunction, taken together with a relatively small number of driver genetic mutations reported for both adult and pediatric liver cancers, shed light on the relevance of epigenetic mechanisms for hepatic tumorigenesis.

Maternal and Birth Characteristics and Childhood Embryonal Solid Tumors: A Population-Based Report from Brazil

BACKGROUND

Several maternal and birth characteristics have been reported to be associated with an increased risk of many childhood cancers. Our goal was to evaluate the risk of childhood embryonal solid tumors in relation to pre- and perinatal characteristics.

METHODS

A case-cohort study was performed using two population-based datasets, which were linked through R software. Tumors were classified as central nervous system (CNS) or non-CNS-embryonal (retinoblastoma, neuroblastoma, renal tumors, germ cell tumors, hepatoblastoma and soft tissue sarcoma). Children aged <6 years were selected. Adjustments were made for potential confounders. Odds ratios (OR) with 95% confidence intervals (CI) were computed by unconditional logistic regression analysis using SPSS.

RESULTS

Males, high maternal education level, and birth anomalies were independent risk factors. Among children diagnosed older than 24 months of age, cesarean section (CS) was a significant risk factor. Five-minute Apgar ≤8 was an independent risk factor for renal tumors. A decreasing risk with increasing birth order was observed for all tumor types except for retinoblastoma. Among children with neuroblastoma, the risk decreased with increasing birth order (OR = 0.82 (95% CI 0.67-1.01)). Children delivered by CS had a marginally significantly increased OR for all tumors except retinoblastoma. High maternal education level showed a significant increase in the odds for all tumors together, CNS tumors, and neuroblastoma.

CONCLUSION

This evidence suggests that male gender, high maternal education level, and birth anomalies are risk factors for childhood tumors irrespective of the age at diagnosis. Cesarean section, birth order, and 5-minute Apgar score were risk factors for some tumor subtypes.

Childhood Neuroblastoma: Incidence and Survival in Argentina. Report from the National Pediatric Cancer Registry, ROHA Network 2000-2012

BACKGROUND

There are reports indicating a low incidence of neuroblastoma (NB) in some developing countries but no conclusive data are available from population-based studies at a national level.

PURPOSE

To describe the incidence and survival of 971 patients with NB in Argentina with data from the National Pediatric Cancer Registry (ROHA), and the impact of age, gender, stage, regional, and socioeconomic indicators on outcome.

METHODS

All cases of NB reported to ROHA (2000-2012) were the subject of the analysis. Annual-standardized incidence rate (ASR) was calculated using the National Vital Statistics and survival was estimated. The extended human development index (EHDI) was used as the socioeconomic indicator.

RESULTS

ASR was 8.3/1,000,000 children (0-14 years) and remained stable along this period. Regional variation in ASR ranged from 3.4 in the Northwest to 9.8 in the Central region, being most marked in the first year of life. Five-year survival rate (SR) was 47%, with no sex difference. For patients older than 18 months, it was 36%, for stage IV 23%, for those born in the Northeast region 38%, and for those with an amplified MYCN 15%. Residents in provinces with a higher EHDI had a better 5-year survival (57% vs. 41% for lower EHDI) and higher ASR (12.3 vs. 5.6 for lower EHDI). Stage and MYCN status showed an independent inferior prognosis.

CONCLUSIONS

ASR of NB in Argentina is lower than in developed countries, with considerable regional variation. SRs are also lower than in developed countries.

Hirschsprung disease and hepatoblastoma: case report of a rare association

CONTEXT

Hirschsprung disease is a developmental disorder of the enteric nervous system that is characterized by absence of ganglion cells in the distal intestine, and it occurs in approximately 1 in every 500,000 live births. Hepatoblastoma is a malignant liver neoplasm that usually occurs in children aged 6 months to 3 years, with a prevalence of 0.54 cases per 100,000.

CASE REPORT

A boy diagnosed with intestinal atresia in the first week of life progressed to a diagnosis of comorbid Hirschsprung disease. Congenital cataracts and sensorineural deafness were diagnosed. A liver mass developed and was subsequently confirmed to be a hepatoblastoma, which was treated by means of surgical resection of 70% of the liver volume and neoadjuvant chemotherapy (ifosfamide, cisplatin and doxorubicin).

CONCLUSION

It is known that Hirschsprung disease may be associated with syndromes predisposing towards cancer, and that hepatoblastoma may also be associated with certain congenital syndromes. However, co-occurrence of hepatoblastoma and Hirschsprung disease has not been previously described. We have reported a case of a male patient born with ileal atresia, Hirschsprung disease and bilateral congenital cataract who was later diagnosed with hepatoblastoma.

Association of TP53 polymorphisms on the risk of Wilms tumor

BACKGROUND

Molecular factors influencing Wilms tumor (WT) development remain largely unknown. TP53 mutations seem to be restricted to the anaplastic WT subtype. However, TP53 polymorphisms do not have a defined role in the disease.

PROCEDURE

To assess the impact of TP53 mutations and polymorphisms (PIN2, PIN3, and PEX4) on risk of development, age at diagnosis, and survival in WT, we analyzed 46 blood DNA samples and 31 fresh tumor DNA samples from 52 patients with WT. Sequencing of TP53 exons 2-11 was performed.

RESULTS

Tumor DNA analysis revealed TP53 pathogenic missense mutations (p.V197M, p.R213Q, p.R248W, and p.R337C) in four samples (12.9%). Blood DNA samples revealed a novel intronic mutation, IVS2 + 37C > T, in one patient (2.2%). Bilaterality was associated with a twofold decrease in survival (P = 0.00037). Diffuse anaplasia also presented a lower survival probability compared to patients with non-anaplastic tumors, or with focal anaplasia (P = 0.045). Patients with a TP53 somatic mutation showed survival probability of 37.5% versus 85.0% for patients with no somatic mutations, although the difference was not statistically significant (P = 0.0706). PIN3 duplicated allele was associated with a 20-month later mean age at diagnosis (P = 0.0084). TP53 PEX4 C allele showed an increased risk for WT development (P = 0.0379). No relationship was found between survival and gender, age at diagnosis, or the less frequent alleles of PIN2, PIN3, and PEX4.

CONCLUSIONS

Our results demonstrate an association between PIN3 and age at diagnosis, as well as an association of PEX4 and risk of development of WT.

Childhood cancer and traffic-related air pollution exposure in pregnancy and early life

BACKGROUND

The literature on traffic-related air pollution and childhood cancers is inconclusive, and little is known on rarer cancer types.

OBJECTIVES

We sought to examine associations between childhood cancers and traffic-related pollution exposure.

METHODS

The present study included children < 6 years of age identified in the California Cancer Registry (born 1998-2007) who could be linked to a California birth certificate (n = 3,590). Controls were selected at random from California birthrolls (n = 80,224). CAlifornia LINE Source Dispersion Modeling, version 4 (CALINE4) was used to generate estimates of local traffic exposures for each trimester of pregnancy and in the first year of life at the address indicated on the birth certificate. We checked our findings by additionally examining associations with particulate matter (≤ 2.5 μm in aerodynamic diameter; PM2.5) pollution measured by community-based air pollution monitors, and with a simple measure of traffic density.

RESULTS

With unconditional logistic regression, a per interquartile range increase in exposure to traffic-related pollution during the first trimester (0.0538 ppm carbon monoxide, estimated using CALINE4) was associated with acute lymphoblastic leukemia [ALL; first trimester odds ratio (OR) = 1.05; 95% CI: 1.01, 1.10]; germ cell tumors (OR = 1.16; 95% CI: 1.04, 1.29), particularly teratomas (OR = 1.26; 95% CI: 1.12, 1.41); and retinoblastoma (OR = 1.11; 95% CI: 1.01, 1.21), particularly bilateral retinoblastoma (OR = 1.16; 95% CI: 1.02, 1.33). Retinoblastoma was also associated with average PM2.5 concentrations during pregnancy, and ALL and teratomas were associated with traffic density near the child's residence at birth.

CONCLUSIONS

We estimated weak associations between early exposure to traffic pollution and several childhood cancers. Because this is the first study to report on traffic pollution in relation to retinoblastoma or germ cell tumors, and both cancers are rare, these findings require replication in other studies.

Global challenges in pediatric oncology

PURPOSE OF REVIEW

Reduction of child mortality is one of the Millennium Development Goals; as low-income and middle-income countries (LMICs) advance toward the achievement of this goal, initiatives aimed at reducing the burden of noncommunicable diseases, including childhood cancer, need to be developed.

RECENT FINDINGS

Approximately 200 000 children and adolescents are diagnosed with cancer every year worldwide; of those, 80% live in LMICs, which account for 90% of the deaths. Lack of quality population-based cancer registries in LMICs limits our knowledge of the epidemiology of pediatric cancer; however, available information showing variations in incidence may indicate unique interactions between environmental and genetic factors that could provide clues to cause. Outcome of children with cancer in LMICs is dictated by late presentation and underdiagnosis, high abandonment rates, high prevalence of malnutrition and other comorbidities, suboptimal supportive and palliative care, and limited access to curative therapies. Initiatives integrating program building with education of healthcare providers and research have proven to be successful in the development of regional capacity. Intensity-graduated treatments adjusted to the local capacity have been developed.

SUMMARY

Childhood cancer burden is shifted toward LMICs; global initiatives directed at pediatric cancer care and control are urgently needed. International partnerships facilitating stepwise processes that build capacity while incorporating epidemiology and health services research and implementing intensity-graduated treatments have been shown to be effective.

Constitutional and somatic methylation status of DMRH19 and KvDMR in Wilms tumor patients

The most frequent epigenetic alterations in Wilms tumor (WT) occur at WT2, assigned to 11p15. WT2 consists of two domains: telomeric domain 1 (DMRH19) that contains the IGF2 gene and an imprinted maternally expressed transcript (H19) and centromeric domain 2 (KvDMR) that contains the genes KCNQ1, KCNQ1OT1 and CDKN1C. In this work, we used pyrosequencing and MS-MLPA to compare the methylation patterns of DMRH19/KvDMR in blood and tumor samples from 40 WT patients. Normal constitutional KvDMR methylation indicated that most of the epigenetic alterations in WT occur at DMRH19. Constitutional DMRH19 hypermethylation (HM DMRH19) was observed in two patients with Beckwith-Wiedemann syndrome. Pyrosequencing and MS-MLPA showed HM DMRH19 in 28/34 tumor samples: 16/34 with isolated HM DMRH19 and 12/34 with concomitant HM DMRH19 and KvDMR hypomethylation, indicating paternal uniparental disomy. With the exception of one blood sample, the MS-MLPA and pyrosequencing findings were concordant. Diffuse or focal anaplasia was present in five tumor samples and was associated with isolated somatic HM DMRH19 in four of them. Constitutional 11p15 methylation abnormalities were present in 5% of the samples and somatic abnormalities in the majority of tumors. Combined analysis of DMRH19/KvDMR by pyrosequencing and MS-MLPA is beneficial for characterizing epigenetic anomalies in WT, and MS-MLPA is useful and reliable for estimation of DNA methylation in a clinical setting.

Perinatal characteristics and retinoblastoma

PURPOSE

The etiology of retinoblastoma remains poorly understood. In the present study, we examined associations between perinatal factors and retinoblastoma risk in California children.

METHODS

We identified 609 retinoblastoma cases (420 unilateral, 187 bilateral, and 2 with laterality unknown) from California Cancer Registry records of diagnoses 1988-2007 among children < 6 years of age. We randomly selected 209,051 controls from California birth rolls. The source of most study data was birth certificates. Multivariable logistic regression was used to examine associations between retinoblastoma and perinatal characteristics.

RESULTS

Bilateral retinoblastoma was associated with greater paternal age [for fathers over 35, crude odds ratio (OR) = 1.73, 95 % confidence interval (CI) 1.20, 2.47] and with twin births (OR = 1.93, 95 % CI 0.99, 3.79). Among unilateral cases, we observed an increased risk among children of US-born Hispanic mothers (OR = 1.34, 95 % CI 1.01, 1.77) while a decreased risk was observed for infants born to mothers with less than 9 years of education (OR = 0.70, 95 % CI 0.49, 1.00), a group that consisted primarily of mothers born in Mexico. We observed that maternal infection in pregnancy with any STD (OR = 3.59, 95 % CI 1.58, 8.15) was associated with bilateral retinoblastoma.

CONCLUSIONS

This study supports the findings of previous investigations reporting associations between parental age, HPV infection, and retinoblastoma.