Childhood cancer: incidence and early deaths in Argentina, 2000-2008

Age-period-cohort effects on incidence trends of childhood leukemia from four population-based cancer registries in Colombia

BACKGROUND

Childhood leukemia (CL) is the most prevalent form of pediatric cancer on a global scale. However, there is a limited understanding of the dynamics of CL incidence in South America, with a specific knowledge gap in Colombia. This study aimed to identify trends in CL incidence and to analyze the effects of age, period, and birth cohort on the risk of leukemia incidence in this population.

METHODS

Information on all newly diagnosed leukemia cases (in general and by subtype) among residents aged 0-18 years and living in the serving areas of population-based cancer registries of Cali (2008-2017), Bucaramanga (2000-2017), Manizales (2003-2017), and Pasto (1998-2018). Estimated annual percent changes (EAPC) in incidence over time and potential changes in the slope of these EAPCs were calculated using joinpoint regression models. The effects of age, period, and cohort in CL incidence trends were evaluated using age-period-cohort models addressing the identifiability issue through the application of double differences.

RESULTS

A total of 966 childhood leukemia cases were identified. The average standardized incidence rate (ASIR) of leukemia was calculated and expressed per 100,000 person-years - observing ASIR of 4.46 in Cali, 7.27 in Bucaramanga, 3.89 in Manizales and 4.06 in Pasto. Concerning CL trends there were no statistically significant changes in EAPC throughout the different periods, however, when analyzed by leukemia subtype, statistically significant changes were observed in the EAPC for both ALL and AML. Analysis of age-period-cohort models revealed that age-related factors significantly underpin the incidence trends of childhood leukemia in these four Colombian cities.

CONCLUSIONS

This study offers valuable insights into the incidence trends of childhood leukemia in four major Colombian cities. The analysis revealed stable overall CL incidence rates across varying periods, predominantly influenced by age-related factors and the absence of cohort and period effects. This information is useful for surveillance and planning purposes for CL diagnosis and treatment in Colombia.

Incidence of childhood cancer in Latin America and the Caribbean: coverage, patterns, and time trends

Objective

To provide a comprehensive overview of geographical patterns (2001-2010) and time trends (1993-2012) of cancer incidence in children aged 0-19 years in Latin America and the Caribbean (LAC) and interpret the findings in the context of global patterns.

Methods

Geographical variations in 2001-2010 and incidence trends over 1993-2012 in the population of LAC younger than 20 years were described using the database of the third volume of the International Incidence of Childhood Cancer study containing comparable data. Age-specific incidence per million person-years (ASR) was calculated for population subgroups and age-standardized (WSR) using the world standard population.

Results

Overall, 36 744 unique cases were included in this study. In 2001-2010 the overall WSR in age 0-14 years was 132.6. The most frequent were leukemia (WSR 48.7), central nervous system neoplasms (WSR 23.0), and lymphoma (WSR 16.6). The overall ASR in age group 15-19 years was 152.3 with lymphoma ranking first (ASR 30.2). Incidence was higher in males than in females, and higher in South America than in Central America and the Caribbean. Compared with global data LAC incidence was lower overall, except for leukemia and lymphoma at age 0-14 years and the other and unspecified tumors at any age. Overall incidence at age 0-19 years increased by 1.0% per year (95% CI [0.6, 1.3]) over 1993-2012. The included registries covered 16% of population aged 0-14 years and 10% of population aged 15-19 years.

Conclusions

The observed patterns provide a baseline to assess the status and evolution of childhood cancer occurrence in the region. Extended and sustained support of cancer registration is required to improve representativeness and timeliness of data for childhood cancer control in LAC.

Epidemiology of childhood acute leukemias in marginalized populations of the central-south region of Mexico: results from a population-based registry

Introduction

Acute leukemias (AL) are the main types of cancer in children worldwide. In Mexico, they represent one of the main causes of death in children under 20 years of age. Most of the studies on the incidence of AL in Mexico have been developed in the urban context of Greater Mexico City and no previous studies have been conducted in the central-south of the country through a population-based study. The aim of the present work was to identify the general and specific incidence rates of pediatric AL in three states of the south-central region of Mexico considered as some of the marginalized populations of Mexico (Puebla, Tlaxcala, and Oaxaca).

Methods

A population-based study was conducted. Children aged less than 20 years, resident in these states, and newly diagnosed with AL in public/private hospitals during the period 2021-2022 were identified. Crude incidence rates (cIR), standardized incidence rates (ASIRw), and incidence rates by state subregions (ASIRsr) were calculated. Rates were calculated using the direct and indirect method and reported per million children under 20 years of age. In addition, specific rates were calculated by age group, sex, leukemia subtype, and immunophenotype.

Results

A total of 388 cases with AL were registered. In the three states, the ASIRw for AL was 51.5 cases per million (0-14 years); in Puebla, it was 53.2, Tlaxcala 54.7, and Oaxaca de 47.7. In the age group between 0-19 years, the ASIRw were 44.3, 46.4, 48.2, and 49.6, in Puebla, Tlaxcala, and Oaxaca, respectively. B-cell acute lymphoblastic leukemia was the most common subtype across the three states.

Conclusion

The incidence of childhood AL in the central-south region of Mexico is within the range of rates reported in other populations of Latin American origin. Two incidence peaks were identified for lymphoblastic and myeloid leukemias. In addition, differences in the incidence of the disease were observed among state subregions which could be attributed to social factors linked to the ethnic origin of the inhabitants. Nonetheless, this hypothesis requires further investigation.

Delay in diagnosis and associated factors among children with cancer admitted at pediatric oncology ward, University of Gondar comprehensive specialized hospital, Ethiopia: a retrospective cross-sectional study

BACKGROUND

Delay in the diagnosis of childhood cancer is one of the major health problem that contribute to decreased survival rates of children particularly in developing nations. Despite advances in the field of pediatric oncology, cancer remains a leading cause of death in children. Diagnosis of childhood cancer as early as possible is crucial to reduce mortality. Therefore, the aim of this study was to assess delay in diagnosis and associated factors among children with cancer admitted to pediatric oncology ward, University of Gondar comprehensive specialized hospital, Ethiopia 2022.

METHOD

Institutional-based retrospective cross-sectional study design was conducted from January1, 2019 to December 31, 2021 at University of Gondar comprehensive specialized hospital. All 200 children were included in the study and Data were extracted through structured check-list. The data were entered using EPI DATA version 4.6 and exported to STATA version 14.0 for data analysis.

RESULTS

From the total of two hundred pediatric patients 44% had delayed diagnosis and the median delay diagnosis was 68 days. Rural residence (AOR = 1.96; 95%CI = 1.08-3.58), absence of health insurance (AOR = 2.21; 95%CI = 1.21-4.04), Hodgkin lymphoma (AOR = 9.36; 95%CI = 2.1-41.72), Retinoblastoma (AOR = 4.09; 95%CI = 1.29-13.02), no referral (AOR = 6.3; 95%CI = 2.15-18.55) and absence of comorbid disease (AOR = 2.14; 95%CI = 1.17-3.94) were significant factors associated with delay in diagnosis.

CONCLUSION AND RECOMMENDATION

Delayed in diagnosis of childhood cancer was relatively lower than previous studies and most influenced by the child's residency, health insurance, type of cancer and comorbid disease. Thus; every effort should be made to promote public and parental understanding of childhood cancer, promote health insurance and referral.

Persistently high incidence rates of childhood acute leukemias from 2010 to 2017 in Mexico City: A population study from the MIGICCL

Introduction

Over the years, the Hispanic population living in the United States has consistently shown high incidence rates of childhood acute leukemias (AL). Similarly, high AL incidence was previously observed in Mexico City (MC). Here, we estimated the AL incidence rates among children under 15 years of age in MC during the period 2010-2017.

Methods

The Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia conducted a study gathering clinical and epidemiological information regarding children newly diagnosed with AL at public health institutions of MC. Crude age incidence rates (cAIR) were obtained. Age-standardized incidence rates worldwide (ASIRw) and by municipalities (ASIRm) were calculated by the direct and indirect methods, respectively. These were reported per million population <15 years of age; stratified by age group, sex, AL subtypes, immunophenotype and gene rearrangements.

Results

A total of 903 AL cases were registered. The ASIRw was 63.3 (cases per million) for AL, 53.1 for acute lymphoblastic leukemia (ALL), and 9.4 for acute myeloblastic leukemia. The highest cAIR for AL was observed in the age group between 1 and 4 years (male: 102.34 and female: 82.73). By immunophenotype, the ASIRw was 47.3 for B-cell and 3.7 for T-cell. The incidence did not show any significant trends during the study period. The ASIRm for ALL were 68.6, 66.6 and 62.8 at Iztacalco, Venustiano Carranza and Benito Juárez, respectively, whereas, other municipalities exhibited null values mainly for AML.

Conclusion

The ASIRw for childhood AL in MC is among the highest reported worldwide. We observed spatial heterogeneity of rates by municipalities. The elevated AL incidence observed in Mexican children may be explained by a combination of genetic background and exposure to environmental risk factors.

Early Deaths in Childhood Cancer in Romania-A Single Institution Study

(1) Background: Survival in childhood cancer has improved significantly over the last decades. However, early deaths (EDs) represent an important number of preventable deaths. Our aim was to provide more insight intoEDs in developing countries. (2) Methods: We conducted a retrospective analysis of patients aged 0–18 years with childhood cancer diagnosed between 1996 and 2008 and admitted in the Institute of Oncology “Prof. Dr. Ion Chiricuta” Cluj-Napoca (IOCN), Romania. After exclusion of patients (pts) older than 18 years at diagnosis, pts with a missing personal identification number and pts with unconfirmed diagnosis of malignancy, we included 783 pts in the final analysis. We defined ED as survival of less than one month after cancer diagnosis. We divided pts in groups according to age, major tumour categories and treatment time periods. (3) Results: ED was registered in 20 pts (2.55%). A total of 16EDs were registered in haematologic malignancies and 4 in solid tumours. Statistical analysis was performed on pts diagnosed with haematological malignancies. A statistically significant higher proportion of patients with performance status (PS) 3 and 4 died within one month after diagnosis (24.1%) than patients admitted with PS 0–2 (1%)—p < 0.01. We found no statistically significant difference regarding ED when comparing male versus female (p = 0.85), age at diagnosis or between the threeperiods of diagnosis (p = 0.7). (4) Conclusions: PS at admission is an important risk factor associated with ED in pts with haematologic malignancies. ED in our institution reflects frequent late presentation for medical care, late diagnosis and referral to specialised centres.

Childhood cancer mortality trends in the Americas and Australasia: An update to 2017

BACKGROUND

Marked reductions in childhood cancer mortality occurred over the last decades in high-income countries and, to a lesser degree, in middle-income countries. This study aimed to monitor mortality trends in the Americas and Australasia, focusing on areas showing unsatisfactory trends.

METHODS

Age-standardized mortality rates per 100,000 children (aged 0-14 years) from 1990 to 2017 (or the last available calendar year) were computed for all neoplasms and 8 leading childhood cancers in countries from the Americas and Australasia, using data from the World Health Organization database. A joinpoint regression was used to identify changes in slope of mortality trends for all neoplasms, leukemia, and neoplasms of the central nervous system (CNS) for major countries.

RESULTS

Over the last decades, childhood cancer mortality continued to decrease by approximately 2% to 3% per year in Australasian countries (ie, Japan, Korea, and Australia), by approximately 1.5% to 2% in North America and Chile, and 1% in Argentina. Other Latin American countries did not show any substantial decrease. Leukemia mortality declined in most countries, whereas less favorable trends were registered for CNS neoplasms, particularly in Latin America. Around 2016, death rates from all neoplasms were 4 to 6 per 100,000 boys and 3 to 4 per 100,000 girls in Latin America, and 2 to 3 per 100,000 boys and approximately 2 per 100,000 girls in North America and Australasia.

CONCLUSIONS

Childhood cancer mortality trends declined steadily in North America and Australasia, whereas they were less favorable in most Latin American countries. Priority must be given to closing the gap by providing high-quality care for all children with cancer worldwide.

LAY SUMMARY

Advances in childhood cancer management have substantially improved the burden of these neoplasms over the past 40 years, particularly in high-income countries. This study aimed to monitor recent trends in America and Australasia using mortality data from the World Health Organization. Trends in childhood cancer mortality continued to decline in high-income countries by approximately 2% to 3% per year in Japan, Korea, and Australia, and 1% to 2% in North America. Only a few Latin American countries showed favorable trends, including Argentina, Chile, and Mexico, whereas other countries with limited resources still lagged behind.

Scaling Up the Surveillance of Childhood Cancer: A Global Roadmap

The World Health Organization recently launched the Global Initiative for Childhood Cancer aiming to substantially increase survival among children with cancer by 2030. The ultimate goal concerns particularly less developed countries where survival estimates are considerably lower than in high-income countries where children with cancer attain approximately 80% survival. Given the vast gap in high-quality data availability between more and less developed countries, measuring the success of the Global Initiative for Childhood Cancer will also require substantial support to childhood cancer registries to enable them to provide survival data at the population level. Based on our experience acquired at the International Agency for Research on Cancer in global cancer surveillance, we hereby review crucial aspects to consider in the development of childhood cancer registration and present our vision on how the Global Initiative for Cancer Registry Development can accelerate the measurement of the outcome of children with cancer.

Childhood cancers in a section of the South African private health sector: Analysis of medicines claims data

Background

Although childhood cancers are rare, increases in incidence have been observed in recent times. There is a paucity of data on the current incidence of childhood cancers in South Africa.

Aim

This study described the epidemiology of childhood cancers in a section of the private health sector of South Africa, using medicines claims data.

Setting

This study was designed on a nationally representative medicine claims database.

Method

A longitudinal open-cohort study employing children younger than 19 years and diagnosed with cancers between 2008 and 2017 was conducted using medicine claims data from a South African Pharmaceutical Benefit Management company. Cases were identified using International Classification of Diseases, Tenth Revision (ICD-10) diagnostic codes C00 to C97, together with a medicine claim reimbursed from oncology benefits. Crude incidence rates were calculated per million persons younger than 19 years on the database and standardised using the Segi 1960 world population. Temporal trends in incidence rates, analysed using the joinpoint regression, were reported as annual percentage changes (APCs).

Results

Overall, 173 new cases of childhood cancers were identified in the database, translating into an age-standardised incidence rate (ASR) of 82.3 per million. Annual incidence of cancer decreased from 76.7 per million in 2008 to 58.2 per million in 2017. More incident cases were identified in males (68.8%). The highest proportion of incident cases was recorded for leukaemias (39.9%), the 5–9 year age group (34.1%) and the Gauteng Province (49.7%).

Conclusion

The incidence of childhood cancers decreased over time in the section of the private health sector studied. Leukaemias were the major drivers of childhood cancer incidence.

Childhood cancer in Latin America: from detection to palliative care and survivorship

BACKGROUND

Treatment options for childhood cancer have improved substantially, although in many low- and middle-income countries survival is lagging behind. Integral childhood cancer care involves the whole spectrum from detection and diagnosis to palliative and survivorship care.

METHODS

Based on a literature review and expert opinions, we summarized current practice and recommendations on the following aspects of childhood cancer in Latin America: diagnostic processes and time to diagnosis, stage at diagnosis, treatments and complications, survivorship programs and palliative care and end-of-life services.

RESULTS

Latin America is a huge and heterogeneous continent. Identified barriers show similar problems between countries, both logistically (time and distance to centers, treatment interruptions) and financially (cost of care, cost of absence from work). Governmental actions in several countries improved the survival of children with cancer, but difficulties persist in timely diagnosis and providing adequate treatment to all childhood cancer patients in institutions with complete infrastructure. Treatment abandonment is still common, although the situation is improving. Cancer care in the region has mostly focused on acute treatment of the disease and has not adequately considered palliative and end-of-life care and monitoring of survivors.

CONCLUSIONS

Decentralizing diagnostic activities and centralizing specialized treatment will remain necessary; measures to facilitate logistics and costs of transportation of the child and caretakers should be implemented. Twinning actions with specialized centers in high income countries for help in diagnosis, treatment and education of professionals and family members have been shown to work. Palliative and end-of-life care as well as childhood cancer survivorship plans are needed.

Non-Hodgkin Lymphoma Epidemiology in Children From 2 Socioeconomic Regions in Mexico: 20-Year Registry (1996-2015)

PURPOSE

We analyzed the epidemiologic characteristics of different types of non-Hodgkin Lymphoma (NHL), excluding Burkitt Lymphoma, in 2 Mexican regions with different socioeconomic status.

MATERIALS AND METHODS

In this surveillance study, we analyzed the incidence rates (cases per million children/year) of different types of NHL according to the ICCC3, registered in 1996-2015, from 2 different socioeconomic regions in Mexico: central and southern, with higher and lower status, respectively.

RESULTS

The principal NHL subgroups were precursor (IIb1), mature B cell (IIb2), mature T/NK cell, and no other specification (NOS; 42.3%, 15.8%, 14.1%, and 27.8%, respectively). In both regions, the overall incidence rates were similar (central=5.3, 95% confidence interval [CI], 4.6-6.1 vs. southern=6.3, 95% CI, 4.6-8.4); also, there were no differences by types (precursor cell LNH, 2.3 vs. 2.5; mature B cell, 0.9 vs. 0.8; mature T/NK cells, 0.8 vs. 0.8; and NOS, 1.4 vs. 2.3). In both regions, a decreasing trend was found (central= -0.17%, 95% CI, -0.03 to -0.3, P=0.04; southern= -0.32%, 95% CI, -0.07 to -0.57, P=0.02), with major reduction of NHL NOS from 1996 to 2000. In both regions, men predominated (2.1:1).

CONCLUSIONS

Socioeconomic status did not influence the incidence rates of NHL. In this study, we found a reduction of NHL NOS, possibly due to better typing.

Social Inequalities Along the Childhood Cancer Continuum: An Overview of Evidence and a Conceptual Framework to Identify Underlying Mechanisms and Pathways

Inequalities in health according to social conditions are regarded as unnecessary and unjust. There is a large body of evidence on inequalities in adult cancer, observable throughout the societies on a national level as well as on a global scale. Socioeconomic influences on health matter at all ages including childhood, for which childhood cancer is the leading cause of disease related death in high-income countries (HICs). Substantial differences in the reported incidence of childhood cancers have been observed globally by socioeconomic development of a population. This is reflected in the higher incidence rates reported for HICs, particularly for acute lymphoblastic leukemia, and for cancer in infants (below 1 year), compared to low- and middle-income countries (LMICs). Considerable inequalities between populations and degree of socioeconomic development are also noted for survival from childhood cancer, with substantially lower survival rates seen in most LMICs compared to HICs. With respect to inequalities by socioeconomic position (SEP) within countries, findings of an association between SEP and childhood cancer risk are diverse and limited to studies from HICs. On the contrary, observations on social inequalities in survival within countries are accumulating and indicate that survival inequalities do not only concern resource-poor countries but also high-income populations including European countries. In turn, a childhood cancer diagnosis in itself may have implications on the parents' socioeconomic situation as well as on the later socioeconomic life after having survived the disease. The underlying mechanisms and causal pathways of these empirically demonstrated social inequalities are poorly understood, although it is of significant public health relevance for any actions or strategies to reduce childhood cancer-related inequity. We propose a conceptual framework on potential underlying mechanism and pathways specifically addressing social inequalities in childhood cancer and after childhood cancer to (i) illustrate potential pathways by which social determinants may create health inequities at different points of the childhood cancer continuum; (ii) illustrate potential pathways by which a childhood cancer diagnosis may impact the socioeconomic situation of the concerned family or the later life of a childhood survivor; and (iii) point out how major determinants may relate to each other.

Incidence of childhood cancer in Costa Rica, 2000-2014: An international perspective

BACKGROUND

Estimating childhood cancer incidence globally is hampered by a lack of reliable data from low- and middle-income countries. Costa Rica is one of the few middle-income countries (MIC) with a long-term high quality nationwide population-based cancer registry.

METHODS

Data on incident cancers in children aged under 15 years reported to the Costa Rica National Cancer Registry between 2000 and 2014 were analyzed by diagnostic group, age, sex, and geographical region and compared with incidence data for Hispanic and Non-Hispanic White (NHW) children in California, USA.

RESULTS

During the 15-year period, 2396 cases of childhood cancer were reported in Costa Rica, resulting in an overall age-standardized incidence rate (ASR) of 140/million. Most frequent cancer types were leukemias (40.5%), malignant central nervous system (CNS) tumors (13.9%), and lymphomas (12.7%). The observed ASR of lymphoid leukemia (46.9/million) ranked high globally. Low rates were found for most solid tumors including malignant CNS tumors, sympathetic nervous system tumors, and soft tissue sarcomas. There was almost no change in incidence rates over time, while geographical variations were observed within Costa Rica. The overall cancer rate in Costa Rica was lower compared to NHW (176.1/million) and Hispanic (161.7/million) children in California.

CONCLUSION

Based on the longstanding registration system, the childhood cancer incidence rates were similar to those observed in other Latin American countries. While a degree of under-ascertainment of cases cannot be excluded, the markedly high leukemia rates, in particular of the lymphoid sub-type deserves further study in this population.

Childhood osteosarcoma: Incidence and survival in Argentina. Report from the National Pediatric Cancer Registry, ROHA Network 2000-2013

BACKGROUND

Differences in incidence and survival in osteosarcoma reports are considerable worldwide.

PURPOSE

This study describes the incidence and survival of patients with osteosarcoma 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

Pediatric patients with osteosarcoma reported to ROHA from 2000 through 2013 were analyzed, the annual age-standardized incidence rate (ASR) was calculated using the National Vital Statistics, and survival was estimated. The extended human development index (EHDI) for each reporting region was used as an indicator of socioeconomic status.

RESULTS

There were 515 cases of osteosarcoma identified, yielding an ASR of 3.2/1,000,000 children (0-14 years old). The ASR did not vary significantly by year of diagnosis but ranged from 4.0/1,000,000 in the Cuyo/Western Central region to 2.7/1,000,000 in the northeast region (P < 0.000). The estimated 5-year survival rate was 45% (95% confidence interval [CI] 44-51%), with no difference by sex, diagnosis year, region, or EHDI score (P > 0.1 in all cases). Survival rate for localized disease was 52% (95% CI 45-57%) and for metastatic 22% (95% CI 15-30%).

CONCLUSIONS

In Argentina, ASR of osteosarcoma is similar to that in high-income countries, but survival is lower in all regions. Future work will focus on identification and reduction of causes of preventable treatment failure.

Clinical and Epidemiological Characteristics of Burkitt Lymphomas in Pediatric Patients from Two Defined Socioeconomic Regions in Mexico

We analyzed clinical and epidemiological characteristics of Burkitt lymphoma (BL) in two defined socioeconomic regions in Mexico: high socioeconomic region (HSER; with two political jurisdictions) and low socioeconomic region (LSER; with three jurisdictions). Of the 63 cases registered in the Childhood Cancer Registry (1996-2013), 45 (71.4%) were from HSER and 18 (28.6%) from LSER. The incidence was higher in the LSER (3.1 vs. 1.4 cases per million children/year). The sporadic form and Stages III/IV predominated in both regions. Only one post-renal transplant (HSER) was found. The male/female ratio was higher in the LSER (5.0 vs. 1.4). The peak incidence was in the 1-4 age group for LSER, and in the 5-9 age group for HSER. This difference in the sporadic BL by socioeconomic regions may be related to different exposure factors.

Incidence and survival of childhood leukemia in Recife, Brazil: A population-based analysis

BACKGROUND

Leukemia is the most common pediatric cancer with incidence rates of around 48 per million for children under 15 years of age. The median age-adjusted incidence rate (AAIR) in children aged 0-14 years in Brazil is 53.3 per million. While overall survival rates for children with leukemia have improved significantly, data for incidence, trends, and relative survival among children and adolescents with leukemia in Recife, Brazil, remain incomplete, which hampers our analyses and provision of the best healthcare. The objective of this report is to provide that data.

METHODS

Data from the Population-Based Cancer Registry of Recife were analyzed from 1998 to 2007. Our analyses included frequencies and AAIR, together with age-specific incidence rates for all leukemias, acute lymphoblastic leukemia, and acute myeloid leukemia. To evaluate incidence trends, joinpoint regression, including annual average percent change, were analyzed. Relative survival was calculated using the life-table method.

RESULTS

One hundred seventy-five cases were identified, 51% in females. The review reduced the not otherwise specified (NOS) leukemia category by 50% and diagnosis by death certificate only from 5.7% to 1.1%. The AAIR for leukemia was 41.1 per million, with a peak among children aged 1-4 (78.3 per million). Incidence trends during the period were stable. The five-year relative survival rate was 69.8%.

CONCLUSIONS

These data represent the incidence rate and survival of childhood leukemia in Recife, located in the northeast region of Brazil, using a high-quality database.

The burden of childhood cancer in Mexico: Implications for low- and middle-income countries

In Mexico, childhood cancer incidence and mortality have increased in the last decade. Through government actions since 2005, the Popular Medical Insurance (PMI) program for childhood cancer was created. The objective of PMI was to offer early cancer diagnosis, standardized treatment regimens, and numerous pediatric oncology residency programs. It has also accredited 55 national hospitals for the care of these children. Current problems still present under the PMI include shortage of pediatric oncologists and nurses and high rate of abandonment of treatment. Our aim is to describe the current scenario of childhood cancer care in Mexico, especially from the perspective of the PMI and how it has impacted human resources, infrastructure, and medical education.

Survival of high-risk pediatric neuroblastoma patients in a developing country

Little information is available about survival of high-risk pediatric neuroblastoma patients in developing countries. We aimed to assess survival among high-risk pediatric neuroblastoma patients in La Plata, Argentina. Individuals eligible for our cohort were aged <20 yr when diagnosed with high-risk neuroblastoma and received cancer-directed therapy including stem cell transplantation at Hospital de Niños Sor Maria Ludovica between February 1999 and February 2015. We estimated overall survival probabilities using an extended Kaplan-Meier approach. Our study population comprised 39 high-risk neuroblastoma patients, of whom 39% were aged >4 yr at diagnosis, 54% were male, and 62% had adrenal neuroblastoma. We observed 18 deaths, and the median survival time of our study population was 1.7 yr. The five-yr overall survival probability was 24% (95% CL: 10%, 41%). In contrast, five-yr survival of high-risk neuroblastoma patients ranges between 23% and 76% in developed countries. Survival among high-risk neuroblastoma patients is generally poor regardless of geographic location, but our results illustrate dramatically worse survival for patients in a developing country. We speculate that the observed survival differences could be attenuated or eliminated with improvements in treatment and supportive care, but addressing these issues will require creative solutions because of resource limitations.

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.

Incidence of Childhood Hodgkin Lymphoma in Mexico by Histologic Subtypes and Socioeconomic Regions

BACKGROUND

Incidence rates of the histologic subtypes of Hodgkin lymphoma (HL) differed with socioeconomic conditions.

MATERIALS AND METHODS

HL cases from the Register of Childhood Cancer (below 15 y of age) for 2 socioeconomic regions were analyzed. Central region has a high socioeconomic index; and the southern region a low index. The incidence rates (cases per million children/year) were estimated according to histologic subtypes, age groups, sex, clinical stages, time to diagnosis, and overall survival by regions.

RESULTS

The overall incidence was greater in the south (6.8 vs. 4.6), principally due to higher incidence of mixed cellularity subtype (3.8 vs. 1.0). In the south, the highest incidence was found in the 5- to 9-year-old group (9.2), whereas in the central region it was found in the 10- to 14-year-old group (7.4). There was a delay of ∼3 weeks in the time to diagnosis (P=0.36) in the south, but no difference in the percentage of advanced stages, adjusted by histologic subtype (61%, III and IV). The overall survival was 71%, differences were identified only for mixed cellularity cases (center=89.2 vs. south=61.5%, P=0.03).

CONCLUSIONS

Incidences of HL subtypes differed in relation to socioeconomic conditions in Mexico. In the south, the incidence of mixed cellularity was higher and there was an earlier peak of presentation.

Early childhood leukemia incidence trends in Brazil

Incidence rates of childhood leukemia vary between different regions of the world. The objective of this study was to test possible trends in incidence rate of early childhood leukemia (children <5 years old at the diagnosis) in Brazil. Data from 18 population-based cancer registries (PBCRs) were analyzed (period 1999-2010). The analysis consisted of frequencies, age-adjusted incidence rates, and joinpoint regression results, including annual average percent change (AAPC) in incidence rates and 95% confidence intervals (CIs). The median age-adjusted incidence rate (AAIR) of overall early childhood leukemia was 61 per million. The AAIR for acute lymphoid leukemia (ALL) was 44 per million and nonlymphoid acute leukemia (NLAL) was 14 per million. The median ALL/NLAL ratio was 3.0, suggesting higher incidence rate of NLAL in these settings. The joinpoint analysis demonstrated increased leukemia incidence rate in João Pessoa (AAPC = 20; 95% CI: 3.5, 39.4) and Salvador (AAPC = 8.68; 95% CI: 1.0, 16.9), respectively, whereas incidence rate in São Paulo PBCR decreased (AAPC = -4.02%; 95% CI: -6.1%, -1.9%). Correlation between ALL AAIR and selected variables of socioeconomic (SES) factors was not observed. Increased AAIR regionally overtime was observed. However, the interpretation for such phenomenon should be cautious because it might reflect the access to health care, diagnosis procedures, and improvement of PBCR´s quality. The observed trend supports the necessity of further ecological studies.

Incidence and Survival of Childhood Cancer in Korea

Purpose

An epidemiologic study of childhood cancer would provide useful information on cancer etiology and development of management guidelines.

Materials and Methods

Data from the Korea National Cancer Incidence Database were used to examine the incidence and survival of cancer in patients aged 0-14 years. Patients were grouped according to the International Classification of Childhood Cancer, 3rd edition. Age-specific and age-standardized incidences per million and estimated annual percentage change (APC) were calculated by sex and age. Five-year relative survival was calculated for four periods from 1993 to 2011.

Results

The study comprised 15,113 patients with malignant neoplasms. Age-standardized incidence rates for all cancers were 134.9 per million children in 1999-2011 and 144.0 and 124.9 per million for males and females, respectively (M/F ratio, 1.2; p < 0.05). The highest incidences were observed for ‘leukemias, myeloproliferative diseases, and myelodysplastic diseases’ (group I) (46.4), ‘central nervous system neoplasms’ (group III) (18.3), and ‘lymphomas and reticuloendothelial neoplasms’ (group II) (13.4). Age-standardized incidence increased from 117.9 in 1999 to 155.3 in 2011, with an APC of 2.4% (95% confidence interval, 2.1 to 2.7). There was a significant increase of APC in ‘neuroblastoma and other peripheral nervous cell tumors’ (group IV) (5.6%) and ‘other malignant epithelial neoplasms and malignant melanomas’ (group XI) (5.6%). The 5-year relative survival rate for all childhood cancers improved significantly from 56.2% (1993-1995) to 78.2% (2007-2011) (males, 56.7% to 77.7%; females, 55.5% to 78.8%).

Conclusion

This study provides reliable information on incidence and survival trends for childhood cancer in Korea.

Childhood cancer incidence patterns by race, sex and age for 2000-2006: a report from the South African National Cancer Registry

Higher childhood cancer incidence rates are generally reported for high income countries although high quality information on descriptive patterns of childhood cancer incidence for low or middle income countries is limited, particularly in Sub-Saharan Africa. There is a need to quantify global differences by cancer types, and to investigate whether they reflect true incidence differences or can be attributed to under-diagnosis or under-reporting. For the first time, we describe childhood cancer data reported to the pathology report-based National Cancer Registry of South Africa in 2000-2006 and compare our results to incidence data from Germany, a high income country. The overall age-standardized incidence rate (ASR) for South Africa in 2000-2006 was 45.7 per million children. We observed substantial differences by cancer types within South Africa by racial group; ASRs tended to be 3-4-fold higher in South African Whites compared to Blacks. ASRs among both Black and White South Africans were generally lower than those from Germany with the greatest differences observed between the Black population in South Africa and Germany, although there was marked variation between cancer types. Age-specific rates were particularly low comparing South African Whites and Blacks with German infants. Overall, patterns across South African population groups and in comparison to Germans were similar for boys and girls. Genetic and environmental reasons may probably explain rather a small proportion of the observed differences. More research is needed to understand the extent to which under-ascertainment and under-diagnosis of childhood cancers drives differences in observed rates.

Registration of childhood cancer: Moving towards pan-European coverage?

Cancer is relatively rare in childhood, but it contributes considerably to childhood mortality, years of life lost per person and late effects in survivors. Large populations need to be covered to set up meaningful studies of these rare conditions. Cancer registries ensure cancer surveillance, thus providing the basis for research as well as policy decisions. In this paper we examine coverage of childhood population by cancer registries in Europe and encourage national cancer registration. Over 200 cancer registries in various stages of development were identified as collecting data on childhood cancer patients in Europe. They cover 52% of the childhood population in the World Health Organisation (WHO) European region and 83% in the European Union (EU). More than 80% of this coverage is ensured by nationwide data collection, which is ongoing in 29 European countries. Overall coverage of the childhood population could increase to around 98%, if the recently established cancer registries start producing results and others improve their quality and dissemination plans. Paediatric cancer registries are being established with increasing frequency even in the areas covered by general cancer registries, and they tend to be national. Compared with regional registration, national cancer registries are more cost-effective, record larger number of cases, they can achieve higher completeness, less biased incidence and survival estimates and they are conditioned for national and international research. National registration of childhood cancer should be the rule in Europe, so that accurate regional, nation-wide and international statistics can provide solid baselines for research, clinical practice and public health policy. Governmental support and stakeholders' involvement are indispensable to guarantee optimal data quality and completeness.

Polymorphic variants of GSTM1, GSTT1, and GSTP1 genes in childhood acute leukemias: A preliminary study in Argentina

BACKGROUND AND AIM

Despite recent major advances in leukemia research, the etiopathogenesis of childhood leukemias remains far elusive. Individual predisposing factors, including polymorphisms in detoxification enzymes, have been implicated in the molecular pathogenesis and heterogeneity of the disease. Genetic polymorphisms of glutathione S-transferases (GSTs) that alter enzyme activity could be an additional factor that increases the risk of acute leukemia, but data are lacking in Argentina. We assessed the association of GST polymorphisms and the susceptibility to childhood leukemia in Argentina by conducting an exploratory case-control study and correlated patients' genotype to clinical and biological features.

METHODS

Deletion polymorphisms in GSTM1 and GSTT1 genes and the single nucleotide polymorphism in GSTP1 c.313A>G (rs1695; p.105Ile>Val) were genotyped by PCR-RFLP in 36 patients and 133 healthy individuals.

RESULTS

GSTM1-null genotype was associated with a lower risk of developing acute leukemia (P = 0.013; OR: 0.31; CI: 0.12-0.80), while GSTP1-GG variants displayed an increased risk (P = 0.01; OR: 3.9; CI: 1.85-8.2). However, no differences were found for GSTT1 gene. Conclusion These preliminary results, to be validated in a larger population from Argentina, suggest that the development of pediatric leukemia may be differentially influenced by polymorphic variants in GST genes.

A population-based study of retinoblastoma incidence and survival in Argentine children

BACKGROUND

An increased incidence of retinoblastoma in some developing countries has been reported but no conclusive data are available from population-based studies at national level.

PURPOSE

To report the incidence and survival of retinoblastoma in Argentina from the National Pediatric Cancer Registry (ROHA) and the influence of socio-economical indicators on outcome.

PROCEDURE

Cases reported to the ROHA (2000-2009) were analyzed. Incidence rates were calculated using National Vital Statistics and survival was estimated. The extended human development index (EHDI) was used as a socio-economical indicator.

RESULTS

With 438 patients reported, an incidence of 5.0 cases per million children 0-14 years old (95% CI 3.5-6.4) was calculated. Median age at diagnosis was significantly higher for children from provinces with lower EHDI; (24 vs. 35 months for unilateral, (P = 0.003) and 9 versus 11.5 months for bilateral retinoblastoma (P = 0.027). The 3-year probability of survival was 0.87 and 0.94 for unilateral and bilateral retinoblastoma, respectively. Residents in provinces with higher EHDI had a better 3-year survival (0.93 vs. 0.77 for lower EHDI, P < 0.0001). Probability of survival was higher for patients treated at tertiary level institutions (P = 0.0015). The combination of low EHDI residence province with no treatment at a tertiary institution was associated with the worst survival outcome. For both, unilateral and bilateral disease, children who died were in average diagnosed at older age.

CONCLUSIONS

The incidence of retinoblastoma in Argentina is comparable to that of developed countries. Retinoblastoma is diagnosed later and survival is lower in the less developed areas of the country.

The role of SIOP as a platform for communication in the global response to childhood cancer

Since the year 2000, there has been a 35% annual decrease in mortality among children under the age of five worldwide. The decrease is mainly attributed to the decrease in childhood epidemic infections, for example, due to vaccination programs. In the near future, this decrease will draw attention to paediatric non-communicable diseases (NCDs), and cancer is one of the most common. Access to care for children with cancer and survival rates have improved dramatically in high-income countries. However, it is important that a global perspective addresses problems in developing countries in particular. To meet this challenge, it is critical that emphasis is placed on demands such as access to care and drugs that are known to be effective, and which can be safely administered in resource-limited settings. Additionally, cancer registries and improved health care structures that include care for children with cancer, are paramount for further progress to increase awareness and the survival of children with cancer. The purpose of this paper is to describe current worldwide interventions to improve childhood cancer from the perspective of the International Society of Paediatric Oncology (SIOP). This global perspective will serve as an introduction to a series of papers from six SIOP continental branches, which will highlight the specific and/or common issues related to children with cancer worldwide. To strengthen the communication among and synergistic effects of various paediatric cancer stakeholders, SIOP could serve as a global platform for a proposed Global Paediatric Cancer Network through the interaction of its continental branches and partner collaborations.