Socioeconomic differences in cancer survival among Swedish children

Early mortality in children with cancer in Denmark and Sweden: The role of social background in a setting with universal healthcare

Socioeconomic differences in overall survival from childhood cancer have been shown previously, but the underlying mechanisms remain unclear. We aimed to investigate if social inequalities were seen already for early mortality in settings with universal healthcare. From national registers, all children diagnosed with cancer at ages 0-19 years, during 1991-2014, in Sweden and Denmark, were identified, and information on parental social characteristics was collected. We estimated odds ratios (OR) and 95% confidence intervals (CI) of early mortality (death within 90 days after cancer diagnosis) by parental education, income, employment, cohabitation, and country of birth using logistic regression. For children with acute lymphoblastic leukaemia (ALL), clinical characteristics were obtained. Among 13,926 included children, 355 (2.5%) died within 90 days after diagnosis. Indications of higher early mortality were seen among the disadvantaged groups, with the most pronounced associations observed for maternal education (ORadj_Low_vs_High 1.65 [95% CI 1.22-2.23]) and income (ORadj_Q1(lowest)_vs_Q4(highest) 1.77 [1.25-2.49]). We found attenuated or null associations between social characteristics and later mortality (deaths occurring 1-5 years after cancer diagnosis). In children with ALL, the associations between social factors and early mortality remained unchanged when adjusting for potential mediation by clinical characteristics. In conclusion, this population-based cohort study indicated differences in early mortality after childhood cancer by social background, also in countries with universal healthcare. Social differences occurring this early in the disease course requires further investigation, also regarding the timing of diagnosis.

Socio-economic and ethnic disparities in childhood cancer survival, Yorkshire, UK

BACKGROUND

Establishing the existence of health inequalities remains a high research and policy agenda item in the United Kingdom. We describe ethnic and socio-economic differences in paediatric cancer survival, focusing specifically on the extent to which disparities have changed over a 20-year period.

METHODS

Cancer registration data for 2674 children (0-14 years) in Yorkshire were analysed. Five-year survival estimates by ethnic group (south Asian/non-south Asian) and Townsend deprivation fifths (I-V) were compared over time (1997-2016) for leukaemia, lymphoma, central nervous system (CNS) and other solid tumours. Hazard ratios (HR: 95% CI) from adjusted Cox models quantified the joint effect of ethnicity and deprivation on mortality risk over time, framed through causal interpretation of the deprivation coefficient.

RESULTS

Increasing deprivation was associated with significantly higher risk of death for children with leukaemia (1.11 (1.03-1.20)) and all cancers between 1997 and 2001. While we observed a trend towards reducing differences in survival over time in this group, a contrasting trend was observed for CNS tumours whereby sizeable variation in outcome remained for cases diagnosed until 2012. South Asian children with lymphoma had a 15% reduced chance of surviving at least 5 years compared to non-south Asian, across the study period.

DISCUSSION

Even in the United Kingdom, with a universally accessible healthcare system, socio-economic and ethnic disparities in childhood cancer survival exist. Findings should inform where resources should be directed to provide all children with an equitable survival outcome following a cancer diagnosis.

Demographic and treatment risk factors of cancer-specific mortality among children and adolescent leukemia patients: a population-based study

Leukemia is the 15th most commonly diagnosed cancer and the 11th leading cause of cancer mortality. The high mortality rate of leukemia could be attributed to numerous factors. Therefore, we aimed to identify the demographic and treatment risk factors influencing mortality among patients diagnosed with leukemia. Patients' data from 1975 to 2016 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. We used the Person's chi-square test to examine the associations among the categorical variables. Kaplan-Meier and Cox regression were applied for univariate and multivariate analyses. Standardized mortality ratios were utilized to compare the mortality rates of leukemia patients and the general US population. We carried out the statistical analysis using SPSS software. A total of 18,880 patients with leukemia were studied. The leukemia incidence was increased in children than in adolescents. Acute lymphoid leukemia (ALL) was the most common type diagnosed among children and adolescents: 10,331 and 4112 patients, respectively. All mortality ratios were significantly higher in leukemia patients compared to the US population. The risk of mortality among leukemia patients was higher among adolescents, females, Black, urban areas with a 20,000 population, and patients not receiving chemotherapy. In contrast, the mortality risk was decreased in patients with higher family incomes, those not treated with radiation, and diagnosed from 2000 to 2016. In conclusion, Leukemia's incidence increases with time. Adolescents, males, Black, in some urban areas, and patients who have not received chemotherapy had the highest mortality risk among leukemia patients.

Prospective registration of symptoms and times to diagnosis in children and adolescents with central nervous system tumors: A study of the Swedish Childhood Cancer Registry

BACKGROUND

The elapsed time taken to diagnose tumors of the central nervous system in children and adolescents varies widely. The aim of the present study was to investigate such diagnostic time intervals at a national level in Sweden as they correlate with clinical features.

METHODS

Data prospectively accumulated over a 4-year period in the Swedish Childhood Cancer Registry from patients aged 0-18 years were pooled, and diagnostic time intervals were analyzed considering tumor location, tumor type, patient age and sex, initial symptoms, and clinical timelines. All six pediatric oncology centers in Sweden contributed to collection of data. Time points for calculating the total diagnostic interval (TDI) defined as the time from symptom onset to diagnosis were reported in 257 of 319 patients (81%).

RESULTS

The time from symptom onset to the first healthcare consultation, median 2.6 weeks, did not vary significantly between patients categorized according to tumor type or location. The median TDI was 8.3 weeks for the 4-year study period. Patients with optic pathway glioma (TDI 26.6 weeks), those with tumors of the spinal cord (TDI 25.9 weeks), and those with midline tumors (TDI 24.6 weeks) had the longest lead times. Additionally, older age, too few initial symptoms, and seeking initial redress outside an emergency ward were factors associated with a longer time to diagnosis.

CONCLUSION

This study identified several factors associated with delayed diagnosis of central nervous system tumors among Swedish children and adolescents. These novel data ought to help direct future efforts toward clinical improvement.

Neighborhood Socioeconomic Deprivation and Mortality in Children with Central Nervous System Tumors

BACKGROUND

Although there is evidence of socioeconomic disparities in survival of children diagnosed with central nervous system (CNS) tumors, the impact of neighborhood socioeconomic deprivation on the survival of these malignancies has not been adequately studied. We investigated the association between area deprivation index (ADI), a measure of neighborhood socioeconomic disadvantage, and pediatric CNS tumor survival.

METHODS

Demographic and clinical characteristics, geocoded addresses at diagnosis, and vital status of pediatric CNS tumor cases (n = 5,477) for the period 1995 to 2017 were obtained from the Texas Cancer Registry. ADI scores were computed for census tracts in Texas using the U.S. Census Bureau 2010 geography. Tracts were classified into quartiles as least, third-most, second-most, and most disadvantaged. Children were mapped to quartiles based on residency at diagnosis. The adjusted hazard ratio (HR) and 95% confidence interval (CI) were calculated.

RESULTS

The results showed a significantly increased HR for death among children in the most (HR, 1.29; 95% CI, 1.09-1.51), second-most (HR, 1.18; 95% CI, 1.01-1.38), and third-most disadvantaged census tracts (HR, 1.18; 95% CI, 1.02-1.37) compared with children in the least disadvantaged tracts.

CONCLUSIONS

Children living in the most disadvantaged neighborhoods experienced a significantly higher risk of mortality, indicating the important role of socioeconomic disparities in the survival of pediatric CNS tumors.

IMPACT

The demographic and socioeconomic disparities identified by this study should be considered when planning treatment strategies for these susceptible groups and thus, lead to a better outcome in socioeconomically disadvantaged children diagnosed with CNS tumors.

Socioeconomic position and prediagnostic health care contacts in children with cancer in Denmark: a nationwide register study

Background

While underlying mechanisms and pathways of social inequalities in cancer survival have been extensively examined in adults, this is less so for children with cancer. Hypothesized mechanisms include prediagnostic utilization of and navigation through the health care system, which may differ by socioeconomic resources of the families. In this nationwide register-based study we investigated the association between measures of family socioeconomic position in relation to prediagnostic health care contacts and stage of disease at diagnosis in children with cancer in Denmark.

Methods

We identified all children diagnosed with a cancer at ages 0–15 years in 1998–2016 (N = 3043) from the Danish Childhood Cancer Registry. We obtained comprehensive information on measures of socioeconomic position, parental health and prediagnostic contacts to both general practitioners and hospitals 24 months prior to diagnosis from various national registries. We fitted multivariable conditional logistic regression models for the association of family socioeconomic and health-related variables with firstly, frequent health care contacts and secondly, advanced stage.

Results

We found higher odds ratios (OR) of frequent both overall and emergency health care contacts in the last 3 months before diagnosis in children from households with short parental education and mixed affiliation to work market, when compared to children with high family socioeconomic position. Further, children of parents with depression or of non-Western origin, respectively, had higher OR for frequent overall and emergency contacts. We found no association between socioeconomic position, parental health and stage of disease.

Conclusion

Families with socioeconomic disadvantage, non-Western origin or depression more frequently utilize prediagnostic health care services, both generally and in the acute setting, indicating that some disadvantaged families may struggle to navigate the health care system when their child is sick. Reassuringly, this was not reflected in disparities in stage at diagnosis. In order to improve the diagnostic process and potentially reduce health care contacts, attention and support should be given to families with a high number of health care contacts over a short period of time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08837-x.

Factors associated with 5- and 10-year survival among a recent cohort of childhood cancer survivors (France, 2000-2015)

BACKGROUND

Childhood cancer survival currently exceeds 80 % five years after diagnosis in high-income countries. In this study, we aimed to describe long-term trends and to investigate socioeconomic and spatial disparities in childhood cancer survival.

METHODS

The study included 28,073 cases recorded in the French National Registry of Childhood Cancers from 2000 to 2015. Contextual census data (deprivation indices, population density, spatial accessibility to general practitioners) were allocated to each case based on the residence at diagnosis. Overall survival (OS) and conditional 10-year OS for 5-year survivors were estimated for all cancers combined and by diagnostic group and subgroup. Comparisons were conducted by sex, age at diagnosis, period of diagnosis, and contextual indicators. Hazard ratios for death were estimated using Cox models.

RESULTS

All cancers combined, the OS reached 82.8 % [95 % CI: 82.4-83.3] at 5 years and 80.8 % [95 % CI: 80.3-81.3] at 10 years. Conditional 10-year OS of 5-year survivors reached 97.5 % [95 % CI: 97.3-97.7] and was higher than 95 % for all subgroups except osteosarcomas and most subgroups of the central nervous system. In addition to disparities by sex, age at diagnosis, and period of diagnosis, we observed a slight decrease in survival for cases living in the most deprived areas at diagnosis, not consistent across diagnostic groups.

CONCLUSION

Our results confirm the high 5-year survival for childhood cancer and show an excellent 10-year conditional survival of 5-year survivors. Additional individual data are needed to clarify the factors underlying the slight decrease in childhood cancer survival observed in the most deprived areas.

Number of siblings and survival from childhood leukaemia: a national register-based cohort study from Sweden

BACKGROUND

Previous studies suggest worse leukaemia survival for children with siblings, but the evidence is sparse, inconsistent and does not consider clinical factors. We explored the associations between number of siblings in the household, birth order and survival from childhood acute lymphoid leukaemia (ALL) and acute myeloid leukaemia (AML).

METHODS

In this nationwide register-based study we included all children aged 1-14, diagnosed with ALL and AML between 1991-mid-2015 in Sweden (n = 1692). Using Cox regression models, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) according to number of siblings and birth order, adjusting for known prognostic and sociodemographic factors.

RESULTS

A tendency towards better ALL survival among children with one, or ≥2, siblings was observed, adjHRs (95% CI): 0.73 (0.49-1.10) and 0.63 (0.40-1.00), respectively. However, this was mainly limited to children with low risk profiles. An indication of better AML survival among children with siblings was seen, adjHRs (95% CI) 0.68 (0.36-1.29) and 0.71 (0.34-1.48) but diminished after adjusting for birth order.

CONCLUSION

Our results do not support previous findings that a larger number of siblings is associated with poorer survival. Inconsistencies might be explained by underlying mechanisms that differ between settings, but chance cannot be ruled out.

Epidemiology and prognostic factors of pediatric brain tumor survival in the US: Evidence from four decades of population data

Brain tumors, a group of heterogeneous diseases, are the second most common cancer and the leading cause of cancer-related deaths in children. Insight into the prognosis of pediatric brain tumor survival has led to improved outcomes and could be further advanced through precision in prognosis. We analyzed the United States SEER population-based dataset of 15,723 pediatric brain tumor patients diagnosed and followed between 1975 and 2016 using a stratified Cox proportional hazards model. Mortality risk declined with increased age at diagnosis, the adjusted hazard ratio (aHR) (95 % confidence interval) was 0.60 (0.55, 0.67) and 0.47 (0.42, 0.52) for ages at diagnosis 1-10 years and 10-19 years, respectively, when compared with infants. Non-Hispanic Caucasian patients showed a lower risk of mortality than non-Hispanic African Americans (1.21 (1.11, 1.32)) and Hispanics (1.21 (1.11, 1.32)). Primary tumor sites, grades, and histology showed substantial heterogeneity in mortality risk. Brainstem (2.62 (2.41, 2.85)) and Cerebrum (1.63 (1.46, 1.81)) had an elevated risk of mortality than lobes. Similarly, Grade II (1.32 (1.07, 1.62)), Grade III (3.39 (2.74, 4.19)), and Grade IV (2.18 (1.80, 2.64)) showed an inflated risk of mortality than Grade I. Compared to low-grade glioma, high-grade glioma (7.92 (7.09, 8.85)), Primitive neuroectodermal tumors (4.72 (4.15, 5.37)), Medulloblastoma (3.11 (2.79, 3.47)), and Ependymal-tumors (2.20 (1.95, 2.48)) had increased risk of mortality. County-level poverty and geographic region showed substantial variation in survival. This large population-based comprehensive study confirmed identified prognostic factors of pediatric brain tumor survival and provided estimates as epidemiologic evidence with greater generalization.

Risk stratification of young adult survivors of cancer to estimate hospital morbidity burden: applicability of a pediatric therapy-based approach

Purpose

Children and young adults (CYA) are at risk of late morbidity following cancer treatment, with risk varying by disease type and treatment received. Risk-stratified levels of aftercare which stratify morbidity burden to inform the intensity of long-term follow-up care, are well established for survivors of cancer under the age of 18 years, utilizing the National Cancer Survivor Initiative (NCSI) approach. We investigated the applicability of risk-stratified levels of aftercare in predicting long-term morbidity in young adults (YA), aged 18–29 years.

Methods

Long-term CYA survivors followed-up at a regional center in the North of England were risk-stratified by disease and treatments received into one of three levels. These data were linked with local cancer registry and administrative health data (Hospital Episode Statistics), where hospital activity was used as a marker of late morbidity burden.

Results

Poisson modelling with incident rate ratios (IRR) demonstrated similar trends in hospital activity for childhood (CH) and YA cancer survivors across NCSI risk levels. NCSI levels independently predicted long-term hospitalization risk in both CH and YA survivors. Risk of hospitalization was significantly reduced for levels 1 (CH IRR 0.32 (95% CI 0.26–0.41), YA IRR 0.06 (95% CI 0.01–0.43)) and 2; CH IRR 0.46 (95% CI 0.42-0.50), YA IRR 0.49 (95% CI 0.37-0.50)), compared with level 3.

Conclusions

The NCSI pediatric late-effects risk stratification system can be effectively and safely applied to cancer patients aged 18–29, independent of ethnicity or socioeconomic position.

Implications for Cancer Survivors

To enhance quality of care and resource utilization, long-term aftercare of survivors of YA cancer can and should be risk stratified through adoption of approaches such as the NCSI risk-stratification model.

Electronic supplementary material

The online version of this article (10.1007/s11764-020-00939-y) contains supplementary material, which is available to authorized users.

Area deprivation is associated with poorer overall survival in children with acute lymphoblastic leukemia

BACKGROUND

Few studies have evaluated social determinants of outcomes disparities for children with acute lymphoblastic leukemia (ALL). We investigated the association of area deprivation index (ADI), a measure of neighborhood socioeconomic disadvantage, with overall survival (OS) among children and adolescents with ALL.

PROCEDURE

We obtained demographic and clinical data, geocoded addresses at diagnosis, and vital status on all Texas children diagnosed with ALL from 1995 to 2011 (N = 4104). Using the US Census Bureau 2010 geography, we computed ADI scores for all census tracts in Texas and grouped the tracts into quartiles: least, third-most, second-most, and most disadvantaged. We mapped children to ADI quartiles based on residence at diagnosis, and estimated OS using Cox regression adjusting for sex, race/ethnicity, age, and metropolitan/nonmetropolitan residence.

RESULTS

Five-year OS ranged from 89% (95% confidence interval [CI] 87-91%) for children in the least disadvantaged tracts to 79% (95% CI 76-81%) for children in the most disadvantaged tracts (P = 4E-7). An elevated hazard ratio (HR) for death was observed for children in the most disadvantaged tracts (HR 1.57, 95% CI 1.23-2.00), and trends toward increased mortality were observed in the third-most and second-most disadvantaged tracts (HR 1.23, 95% CI 0.97-1.57 and HR 1.27, 95% CI 0.99-1.62, respectively). In stratified analyses, area disadvantage was more strongly associated with OS in males than females.

CONCLUSIONS

Neighborhood socioeconomic disadvantage is associated with inferior OS in this analysis of over 4100 children with ALL, highlighting the substantial contributions of social-environmental factors to childhood cancer survival. This association was stronger in males than females.

Childhood cancer: Survival, treatment modalities, late effects and improvements over time

Since the 1960s, paediatric oncologists have gradually become better organised in large study groups and participation in clinical trials is today considered as the standard of care, with most children with cancer in Europe and North America being enrolled on available treatment protocols. Chemotherapy is nowadays the main element of therapy, but irradiation is still required for some patients. With the advent of multimodality therapy and supportive care, five-year cancer survival exceeds 80 % in most European and North American countries today. The substantial improvements in survival led to a constantly growing population of childhood cancer survivors. Concerns regarding the risk of late effects of the intensive cancer treatment at a young age, together with increasing numbers of survivors, have directed attention towards survivorship research. Survivors of childhood cancer are at longstanding risk of various severe somatic and mental health conditions attributable to the cancer and its treatment, as well as adverse social and socioeconomic consequences, and diminished psychological well-being and quality of life. It is, however, important to stress that some survivors have no or very mild adverse health conditions. Nevertheless, joint efforts are warranted for the care and long-term follow-up of childhood cancer patients. With this article, we provide a comprehensive overview of improvements in survival and treatment modalities over time, as well as the related somatic and mental late effects, and social and socioeconomic difficulties that these children might encounter later in life.

Brain cancer survival in Canada 1996-2008: effects of sociodemographic characteristics

Background

Literature suggests that factors such as rural residence and low socioeconomic status (ses) might contribute to disparities in survival for Canadian cancer patients because of inequities in access to care. However, evidence specific to brain cancer is limited. The present research estimates the effects of rural or urban residence and ses on survival for Canadian patients diagnosed with brain cancer.

Methods

Adults diagnosed with primary malignant brain tumours during 1996-2008 were identified through the Canadian Cancer Registry. Brain tumours were classified using International Classification of Diseases for Oncology (3rd edition) site and histology codes. Hazard ratios (hrs) and 95% confidence intervals (cis) were estimated using Cox proportional hazards models. Events were restricted to individuals whose underlying cause of death was cancer-related. Postal codes were used to match patient records with Statistics Canada data for rural or urban residence and neighbourhood income as a surrogate measure of ses.

Results

Of 25,700 patients included in the analysis, 78% died during the study period, 21% lived in rural areas, and 19% were in the lowest income group. A modest variation in survival by rural compared with urban residence was observed for patients with glioblastoma (first 5 weeks after diagnosis hr: 0.86; 95% ci: 0.79 to 0.99) and oligoastrocytoma (first 3 years after diagnosis hr: 1.41; 95% ci: 1.03 to 1.93). Small effects of low compared with high income were seen for patients with glioblastoma (first 1.5 years after diagnosis hr: 1.15; 95% ci: 1.08 to 1.22) and diffuse astrocytoma (first 6 months after diagnosis hr: 1.17; 95% ci: 1.00 to 1.36).

Conclusions

Our analysis did not yield evidence of strong effects of rural compared with urban residence or ses strata on survival in brain cancer. However, some variation in survival for patients with specific histologies warrants further research into the mechanisms by which rural or urban residence and income stratum influences survival.

Association between maternal education and survival after childhood cancer

BACKGROUND

Several nonbiological factors, including socioeconomic status indicators and other family characteristics, influence survival from childhood cancers. Our study explores the association between parental education and childhood cancer survival.

METHODS

The specialized Childhood Cancer Registry of the Piedmont region in Italy provided data on all the cases (aged 0-14) diagnosed with cancer in the period 1976-2011 who resided in the city of Turin (capital of the Piedmont region) at least once since 1971. Information on parental education was extracted from the Turin Longitudinal Study by record linkage. The association between parental educational level and survival was estimated using Cox regression.

RESULTS

The study included 949 children. We observed a disadvantage in the overall survival for children of less educated mothers. No such effect was observed for paternal education. The effect of maternal education was particularly strong for central nervous system tumors (hazard ratios, 2.9; 95% confidence interval, 1.1-8.0). A similar effect, though smaller in magnitude, was observed for leukemia and embryonal tumors, whereas the estimates for lymphoma were imprecise.

CONCLUSIONS

Our study shows an association between maternal educational level and survival in children with central nervous system tumors, a diagnosis that often requires long-lasting treatment and special care. Giving support to the families of affected children to provide them the optimal care has the potential to improve children's cancer treatment outcomes.

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.

Impact of parental socioeconomic factors on childhood cancer mortality: a population-based registry study

INTRODUCTION

Parental socioeconomic status has been proposed to have an influence on childhood cancer mortality even in high-income countries. Our study investigated the influence of parental socioeconomic factors on childhood cancer mortality.

MATERIAL AND METHODS

We identified 4437 patients diagnosed with cancer under the age of 20 from 1990 to 2009 and their parents from the Finnish cancer and central population registers. Information on death from primary cancer during five-year follow-up and parental socioeconomic factors was obtained from Statistics Finland. Poisson regression modeling was used to estimate hazard ratios (HRs) for factors related to cause-specific mortality and recursive tree based survival analysis to identify important risk factors and interactions.

RESULTS

Mortality was lower in the highest quartile of combined parental disposable income (HR 0.68, CI 95% 0.52-0.89) compared to the lowest quartile. In the most recent diagnostic period from 2000 to 2009, highest attained education of either parent being post-secondary predicted lower mortality (HR 0.73, CI 95% 0.60-0.88) compared to parents who had attained primary or lower education.

CONCLUSION

Despite high quality public health care and comprehensive social security, both high parental income and education were associated with lower mortality after childhood cancer. Lower health literacy and financial pressures limiting treatment adherence may explain higher mortality in children with less educated parents and parents with lower income. Motivation and support during treatment and follow-up period is needed concerning the families of these patients.

Survival After Childhood Cancer-Social Inequalities in High-Income Countries

Despite substantial improvements in survival from childhood cancer during the last decades, there are indications that survival rates for several cancer types are no longer improving. Moreover, evidence accumulates suggesting that socioeconomic and sociodemographic factors may have an impact on survival also in high-income countries. The aim of this review is to summarize the findings from studies on social factors and survival in childhood cancer. Several types of cancer and social factors are included in order to shed light on potential mechanisms and identify particularly affected groups. A literature search conducted in PubMed identified 333 articles published from December 2012 until June 2018, of which 24 fulfilled the inclusion criteria. The findings are diverse; some studies found no associations but several indicated a social gradient with higher mortality among children from families of lower socioeconomic status (SES). There were no clear suggestions of particularly vulnerable subgroups, but hematological malignancies were most commonly investigated. A wide range of social factors have been examined and seem to be of different importance and varying between studies. However, potential underlying mechanisms linking a specific social factor to childhood cancer survival was seldom described. This review provides some support for a relationship between lower parental SES and worse survival after childhood cancer, which is a finding that needs further attention. Studies investigating predefined hypotheses involving specific social factors within homogenous cancer types are lacking and would increase the understanding of mechanisms involved, and allow targeted interventions to reduce health inequalities.

Utilisation of primary care before a childhood cancer diagnosis: do socioeconomic factors matter?: A Danish nationwide population-based matched cohort study

OBJECTIVES

Early diagnosis of childhood cancer is critical. Nevertheless, little is known about the potential role of inequality. This study aims to describe the use of primary care 2 years before a childhood cancer diagnosis and to investigate whether socioeconomic factors influence the use of consultations and diagnostic tests in primary care.

DESIGN

A national population-based matched cohort study.

SETTING AND PARTICIPANTS

This study uses observational data from four Danish nationwide registers. All children aged 0-15 diagnosed with cancer during 2008-2015 were included (n=1386). Each case was matched based on gender and age with 10 references (n=13 860).

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was additional rates for consultations and for invoiced diagnostic tests for children with cancer according to parental socioeconomic factors. Furthermore, we estimated the association between socioeconomic factors and frequent use of consultations, defined as at least four consultations, and the odds of receiving a diagnostic test within 3 months of diagnosis.

RESULTS

Children with cancer from families with high income had 1.46 (95% CI 1.23 to 1.69) additional consultations 3 months before diagnosis, whereas children from families with low income had 1.85 (95% CI 1.60 to 2.11) additional consultations. The highest odds of frequent use of consultations was observed among children from low-income families (OR: 1.94, 95% CI 1.24 to 3.03). A higher odds of receiving an invoiced diagnostic test was seen for children from families with mid-educational level (OR: 1.46, 95% CI 1.09 to 1.95).

CONCLUSION

We found a socioeconomic gradient in the use of general practice before a childhood cancer diagnosis. This suggests that social inequalities exist in the pattern of healthcare utilisation in general practice.

Survival and mortality rates of Wilms tumour in Southern and Eastern European countries: Socioeconomic differentials compared with the United States of America

BACKGROUND

Despite recent therapeutic advancements, Wilms tumour (WT) presents remarkable survival variations. We explored mortality and survival patterns for children (0-14 years) with WT in 12 Southern and Eastern European (SEE) countries in comparison with the United States of America (USA).

METHODS

A total of 3966 WT cases (0-14 years) were registered by a network of SEE childhood cancer registries (N:1723) during available registration periods circa 1990-2016 and surveillance, epidemiology, and end results program (SEER) (N:2243; 1990-2012); mortality data were provided by the respective national statistical services. Kaplan-Meier curves and Cox proportional hazards models were used to assess the role of age, sex, year of diagnosis, urbanisation and Human Development Index (HDI) on overall survival (OS).

RESULTS

Persisting regional variations shape an overall 78% 5-year OS in the participating SEE countries, lagging behind the USA figure (92%, p=0.001) and also reflected by higher SEE mortality rates. Worth mentioning is the gradually escalating OS in SEE (hazard ratio [HR]_{5-year increment}:0.67, 95% confidence interval [CI]:0.60, 0.75) vs. a non-significant 10% improvement in the SEER data, which had a high starting value. OS differentials [two-fold less favourable among children aged 10-14 years, boys and those living in rural SEE areas (HR:1.37; CI:1.10-1.71) or countries with inferior HDI (2-3-fold)] were minimal in the USA.

CONCLUSIONS

Children with WT residing in SEE countries do not equally enjoy the substantial survival gains, especially for those living in rural areas and in lower HDI countries. Noteworthy are steep and sizeable survival gains in SEE along with the newly presented Greek data pointing to achievable survival goals in SEE despite the financial crisis.

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.

Survival from tumours of the central nervous system in Danish children: Is survival related to family circumstances?

Little is known about social inequalities in childhood cancer survival. We investigated the impact of family circumstances on survival from paediatric central nervous system (CNS) tumours in a nationwide, register-based cohort of Danish children. All children born between 1973 and 2006 and diagnosed with a CNS tumour before the age of 20 years (N = 1,261) were followed until 10 years from diagnosis. Using Cox proportional hazards models, the impact of various family characteristics on overall survival was estimated. Hazard ratios (HRs) for all CNS tumours combined did not show strong associations between survival and any family characteristic. Analyses by CNS tumour subtypes showed reduced survival for children with glioma when living outside of Copenhagen (HR 1.55; CI 1.03; 2.35). For embryonal CNS tumours, the number of full siblings was associated with worse survival (HR for having 3+ siblings 3.60; CI 1.52; 8.53) and a trend of better survival was observed for children with parents of younger age at child's diagnosis and poorer survival of children with parents of older age. Despite free and uniform access to health care services, some family circumstances appear to affect survival from specific CNS tumour types in Danish children. Further research is warranted to gain a more comprehensive understanding of the impact of family factors on childhood cancer survival in other populations and to elaborate underlying mechanisms and pathways of those survival inequalities observed.

Lower socioeconomic status is independently associated with shorter survival in Hodgkin Lymphoma patients-An analysis from the Brazilian Hodgkin Lymphoma Registry

Socioeconomic status (SES) is a well-known determinant of outcomes in cancer. The purpose of this study was to analyze the impact of the SES on the outcomes of Hodgkin lymphoma (HL) patients from the Brazilian Prospective HL Registry. SES stratification was done using an individual asset/education-based household index. A total of 624 classical HL patients with diagnosis from January/2009 to December/2014, and treated with ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine), were analyzed. The median follow-up was 35.6 months, and 33% were classified as lower SES. The 3-year progression- free survival (PFS) in higher and lower SES were 78 and 64% (p < 0.0001), respectively. The 3-year overall survival (OS) in higher and lower SES were 94 and 82% (p < 0.0001), respectively. Lower SES patients were more likely to be ≥ 60 years (16 vs. 8%, p = 0.003), and to present higher risk International Prognostic score (IPS) (44 vs. 31%, p = 0.004) and advanced disease (71 vs. 58%, p = 0.003). After adjustments for potential confounders, lower SES remained independently associated with poorer survival (HR = 3.12 [1.86-5.22] for OS and HR = 1.66 [1.19-2.32] for PFS). The fatality ratio during treatment was 7.5 and 1.3% for lower and higher SES (p = 0.0001). Infections and treatment toxicity accounted for 81% of these deaths. SES is an independent factor associated with shorter survival in HL in Brazil. Potential underlying mechanisms associated with the impact of SES are delayed diagnosis and poorer education. Educational and socio-economic support interventions must be tested in this vulnerable population.

Is there a socioeconomic variation in survival from renal tumours in children and young people resident in northern England (1968-2012)?

BACKGROUND

Despite strong evidence of a social gradient in cancer survival among UK adults, studies in children and young people remain inconclusive and have not included renal tumours. This study investigated the relationship between socioeconomic status and survival from renal tumours among children and young people.

PROCEDURE

Kaplan-Meier estimation and Cox regression were used to analyse survival for all 209 renal tumours in children and young people (0-24 years) diagnosed 1968-2012 and registered by a specialist population-based registry. Sociodemographic and clinicopathologic variables, including paternal occupation at birth, were also analysed.

RESULTS

No significant disparity in overall renal tumour and Wilms tumour (WT) survival was observed according to paternal social class [p=0.988 and 0.808, respectively]. The strongest predictor of survival was stage, with late stage (III-IV) disease having a 4-fold higher risk of death compared to early stage (I-II) disease [p<0.001]. Similarly, high mortality-risk was seen for late stage WT in children aged 0-14 years (Hazard Ratio=6.37; 95% CI=2.60-15.59).

CONCLUSIONS

This study did not detect a significant social gradient in renal tumour survival. The identification of tumour stage as a strong predictor of survival irrespective of age, necessitates the development of appropriate public health interventions that target early diagnosis and treatment.

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.

Treatment outcomes for Hodgkin lymphoma: First report from the Brazilian Prospective Registry

Data about Hodgkin lymphoma (HL) in developing countries are scarce and suggest the existence of substantial disparities in healthcare and outcomes in large areas of the world. In 2009, a prospective registry of HL was implemented in Brazil. Web-based data were contributed by 20 institutions across the country participating in the Brazilian Prospective Hodgkin's Lymphoma Registry. The aim of this study was to present the clinical features and outcomes of newly diagnosed patients with HL aged 13 to 90 years. Multivariate Cox regression models were used to estimate progression-free (PFS) and overall survival (OS) by clinical factors. A total of 674 patients with classical HL were analysed, with a median follow-up of 37 months. Median age was 30 years (13-90). The median time from the onset of symptoms to diagnosis was 6 months (0-60). Only 6% of patients had early favourable disease, while 65% had advanced disease. Stage IVB was present in 26% and a high-risk International Prognostic Score in 38%. Doxorubicin, bleomycin, vinblastine, and dacarbazine was used in 93%. The median dose of radiotherapy was 36 Gy for localized disease and 32 Gy for advanced disease. The 3 year PFS in early favourable, early unfavourable, and advanced disease were 95%, 88%, and 66%, respectively. High-risk International Prognostic Score, advanced disease, and age greater than or equal to 60 were independently associated with poorer PFS and OS; performance status greater than or equal to 2 was also associated with a poorer OS. Poor-risk patients predominated. Radiation doses for localized disease appear higher than current recommendations. Outcomes appear inferior in developing countries than in developed countries. Delayed diagnosis is probably a major factor underlying these findings. Scattered reports from developing nations suggest that many aspects of standard care in developed countries remain unmet needs for populations living in developing countries. The present report contributes to this body of data, with a proper description of what is currently achieved in urban areas in Brazil.

Adult children's socioeconomic resources and mothers' survival after a breast cancer diagnosis: a Swedish population-based cohort study

OBJECTIVES

Socioeconomic inequalities in survival after breast cancer persist worldwide. We aim to determine whether adult offspring's socioeconomic resources contribute to inequalities in mothers' survival after breast cancer.

METHODS

14 231 women, aged 65-79 years, with a child aged ≥30 years and a first primary diagnosis of breast cancer in the National Cancer Register between 2001 and 2010 were followed until death, 10 years after diagnosis, or end of study (December 2015). Relative survival proportions and excess mortality within 10 years of diagnosis by strata of offspring's education level and disposable income were estimated using flexible parametric models accounting for measures of mothers' socioeconomic position and expected mortality in the general population.

RESULTS

4292 women died during 102 236 person-years of follow-up. Crude 10-year relative survival proportions for mothers of children with >14, 12-14 and <12 years of education were 0.89 (0.87 to 0.91), 0.87 (0.85 to 0.89) and 0.79 (0.76 to 0.81), respectively. Compared with mothers of children with >14 years of education, mothers of children with <12 or 12-14 years of education had substantially higher excess mortality (excess HR 1.69 (1.38 to 2.07) and 1.22 (1.00 to 1.48), respectively). Higher mortality did not differ between tertiles of offspring's disposable income.

CONCLUSIONS

Adult offspring's education level may contribute to inequalities in mothers' survival after breast cancer. Clinicians should be aware of the educational context beyond the individual and women with less educated offsprings may require extra support. This should be considered in future research, policy frameworks and interventions aimed at reducing survival inequalities.