Risk factors for childhood brain tumours: A systematic review and meta-analysis of observational studies from 1976 to 2022

BACKGROUND

Childhood brain tumours (CBTs) are the leading cause of cancer death in children under the age of 20 years globally. Though the aetiology of CBT remains poorly understood, it is thought to be multifactorial. We aimed to synthesize potential risk factors for CBT to inform primary prevention.

METHODS

We conducted a systematic review and meta-analysis of epidemiological studies indexed in the PubMed, Web of Science, and Embase databases from the start of those resources through 27 July 2023. We included data from case-control or cohort studies that reported effect estimates for each risk factor around the time of conception, during pregnancy and/or during post-natal period. Random effects meta-analysis was used to estimate summary effect sizes (ES) and 95% confidence intervals (CIs). We also quantified heterogeneity (I2) across studies.

FINDINGS

A total of 4040 studies were identified, of which 181 studies (85 case-control and 96 cohort studies) met our criteria for inclusion. Of all eligible studies, 50% (n = 91) were conducted in Europe, 32% (n = 57) in North America, 9% (n = 16) in Australia, 8% (n = 15) in Asia, 1% (n = 2) in South America, and none in Africa. We found associations for some modifiable risk factors including childhood domestic exposures to insecticides (ES 1.44, 95% CI 1.20-1.73) and herbicides (ES 2.38, 95% CI 1.31-4.33). Maternal domestic exposure to insecticides (ES 1.45, 95% CI 1.09-1.94), maternal consumption of cured meat (ES 1.51, 95% CI 1.05-2.17) and coffee ≥ 2 cups/day (ES 1.45, 95% 95% CI 1.07-1.95) during pregnancy, and maternal exposure to benzene (ES 2.22; 95% CI 1.01-4.88) before conception were associated with CBTs in case-control studies. Also, paternal occupational exposure to pesticides (ES 1.48, 95% CI 1.23-1.77) and benzene (ES 1.74, 95% CI 1.10-2.76) before conception and during pregnancy were associated in case-control studies and in combined analysis. On the other hand, assisted reproductive technology (ART) (ES 1.32, 95% CI 1.05-1.67), caesarean section (CS) (ES 1.12, 95% CI 1.01-1.25), paternal occupational exposure to paint before conception (ES 1.56, 95% CI 1.02-2.40) and maternal smoking > 10 cigarettes per day during pregnancy (ES 1.18, 95% CI 1.00-1.40) were associated with CBT in cohort studies. Maternal intake of vitamins and folic acid during pregnancy was inversely associated in cohort studies. Hormonal/infertility treatment, breastfeeding, child day-care attendance, maternal exposure to electric heated waterbed, tea and alcohol consumption during pregnancy were among those not associated with CBT in both case-control and cohort studies.

CONCLUSION

Our results should be interpreted with caution, especially as most associations between risk factors and CBT were discordant between cohort and case-control studies. At present, it is premature for any CBT to define specific primary prevention guidelines.

Cohort profile: the United Kingdom Childhood Cancer Study (UKCCS) - a UK-wide population-based study examining the health of cancer survivors

PURPOSE

The United Kingdom Childhood Cancer Study's (UKCCS's) matched cohort was established to examine the longer term morbidity and mortality of individuals previously diagnosed with cancer before 15 years of age, comparing future healthcare patterns in 5-year cancer survivors to baseline activity seen in age- and sex-matched individuals from the general population.

PARTICIPANTS

Predicated on a national childhood cancer case-control study conducted in the early 1990s (4430 cases, 9753 controls) in England, Scotland and Wales, the case population comprises 3125 cancer survivors (>5 years), and the control population 7156 age- and sex-matched individuals from the general population who did not have cancer as a child. Participants are now being followed up via linkage to national administrative healthcare databases (deaths, cancers and secondary care hospital activity).

FINDINGS TO DATE

Enabling the creation of cohorts with minimal selection bias and loss to follow-up, the original case-control study registered all newly diagnosed cases of childhood cancer and their corresponding controls, regardless of their family's participation. Early findings based on the registered case population found marked survival variations with age and sex across subtypes and differences with deprivation among acute lymphoblastic leukaemia (ALL) survivors. More recently, comparing the health-activity patterns of the case and control populations revealed that survivors of childhood ALL experienced excess outpatient and inpatient activity across their teenage/young adult years. Adding to increased risks of cancer and death and involving most clinical specialties, excesses were not related to routine follow-up monitoring and showed no signs of diminishing over time.

FUTURE PLANS

With annual linkage updates, the UKCCS's maturing population-based matched cohorts provide the foundation for tracking the health of individuals through their lifetime. Comparing the experience of childhood cancer survivors to that of unaffected general-population counterparts, this will include examining subsequent morbidity and mortality, secondary care hospital activity and the impact of deprivation on longer term outcomes.

Breastfeeding and risk of childhood brain tumors: a report from the Childhood Cancer and Leukemia International Consortium

PURPOSE

Studies report mixed findings regarding the association of breastfeeding with childhood brain tumors (CBT), the leading causes of cancer-related mortality in young people. Our objective was to determine whether breastfeeding is associated with CBT incidence.

METHODS

We pooled data on N = 2610 cases with CBT (including 697 cases with astrocytoma, 447 cases with medulloblastoma/primitive neuroectodermal tumor [PNET], 167 cases with ependymoma) and N = 8128 age- and sex-matched controls in the Childhood Cancer and Leukemia International Consortium. We computed unconditional logistic regression models to estimate the odds ratio (OR) and 95% confidence interval (CI) of CBT, astrocytoma, medulloblastoma/PNET, and ependymoma according to breastfeeding status, adjusting for study, sex, mode of delivery, birthweight, age at diagnosis/interview, maternal age at delivery, maternal educational attainment, and maternal race/ethnicity. We evaluated any breastfeeding versus none and breastfeeding ≥ 6 months versus none. We subsequently performed random effects meta-analysis to confirm our findings, identify potential sources of heterogeneity, and evaluate for outliers or influential studies.

RESULTS

Breastfeeding was reported by 64.8% of control mothers and 64.5% of case mothers and was not associated with CBT (OR 1.04, 95% CI 0.94-1.15), astrocytoma (OR 1.01, 95% CI 0.87-1.17), medulloblastoma/PNET (OR 1.11, 95% CI 0.93-1.32), or ependymoma (OR 1.06, 95% CI 0.81-1.40). Results were similar when we restricted to breastfeeding ≥ 6 months and in meta-analyses.

CONCLUSION

Our data suggest that breastfeeding does not protect against CBT.

Maternal infections and medications in pregnancy: how does self-report compare to medical records in childhood cancer case-control studies?

BACKGROUND

Studies examining the potential impact of mothers' health during pregnancy on the health of their offspring often rely on self-reported information gathered several years later. To assess the validity of this approach, we analysed data from a national case-control study of childhood cancer (diagnosed <15 years) that collected health information from both interviews and medical records.

METHODS

Mothers' interview reports of infections and medications in pregnancy were compared with primary care records. Taking clinical diagnoses and prescriptions as the reference, sensitivity and specificity of maternal recall along with kappa coefficients of agreement were calculated. Differences in the odd ratios estimated using logistic regression for each information source were assessed using the proportional change in the odds ratio (OR).

RESULTS

Mothers of 1624 cases and 2524 controls were interviewed ∼6 years (range 0-18 years) after their child's birth. Most drugs and infections were underreported; in general practitioner records, antibiotic prescriptions were nearly three times higher and infections >40% higher. Decreasing with increasing time since pregnancy, sensitivity was ⩽40% for most infections and all drugs except 'anti-epileptics and barbiturates' (sensitivity 80% among controls). ORs associated with individual drug/disease categories that were based on self-reported data varied from 26% lower to 26% higher than those based on medical records; reporting differences between mothers of cases and controls were not systematically in the same direction.

CONCLUSIONS

The findings highlight the scale of under-reporting and poor validity of questionnaire-based studies conducted several years after pregnancy. Future research using prospectively collected data should be encouraged to minimize measurement errors.

Parental occupational exposure to combustion products, metals, silica and asbestos and risk of childhood leukaemia: Findings from the Childhood Cancer and Leukaemia International Consortium (CLIC)

Parental occupational exposures around conception (father) or during pregnancy (mother) have been hypothesized as potential predisposing factors for childhood leukaemia. We investigated parental exposure to several known occupational carcinogens and childhood leukaemia risk. We conducted a pooled analysis using case-control data from four European countries (3362 childhood leukemia cases and 6268 controls). Parental occupational exposures to polycyclic aromatic hydrocarbons (PAH), diesel engine exhaust (DEE), chromium, nickel, crystalline silica, and asbestos were assessed by a general population job-exposure matrix. We estimated odd ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression models for all childhood leukaemia combined, by leukaemia type (ALL and AML) and by ALL subtype (B-lineage and T-lineage). We found an association between high paternal occupational exposure to crystalline silica and childhood ALL (OR 2.20, CI 1.60-3.01) with increasing trend from no exposure to high exposure (P = <0.001), and also for AML (OR 2.03, CI 1.04-3.97; P for trend = 0.008). ORs were similar for B- and T-lineage ALL. For ALL, ORs were also slightly elevated with wide confidence intervals for high paternal occupational exposure to chromium (OR 1.23, CI 0.77-1.96), and DEE (OR 1.21, CI 0.82-1.77). No associations were observed for paternal exposures to nickel, PAH and asbestos. For maternal occupational exposure we found several slightly elevated odds ratios but mostly with very wide confidence intervals due to low numbers of exposed mothers. This is a first study suggesting an association between fathers' occupational exposure to crystalline silica and an increased risk of childhood leukaemia in their offspring. As this association was driven by certain occupations (field crop farmers and miners) where other potentially relevant exposures like pesticides and radon may also occur, more research is needed to confirm our findings of an association with crystalline silica, and if so, mechanistic studies to understand the pathways.

Abstract 1448: Novel specific susceptibility loci identified for pediatric and adult ependymoma in first histology-specific genome-wide association study

Despite extensive research, a small proportion of the variants contributing to the genetic architecture of brain tumors have been reported. The published GWAS have been largely performed on pooled histological subtypes of glioma and most of these studies have been conducted primarily for adult tumors. Therefore, we aimed to perform the first GWAS specifically for ependymoma to identify the genetic variants associated with the risk of these tumors and to investigate the similarities/differences between the genetic architectures of adult and pediatric ependymomas.

Germline SNP-array data of ependymoma cases were obtained from nine studies or biobanks across the United States and Europe. Controls were randomly selected with the ratio of 10:1 from three of those studies and a separate publicly available database. Additionally, germline whole genome sequencing data on cases and controls from St Jude Cloud were utilized. In total, 483 pediatric cases and 265 adult cases and 5592 controls were included. The same quality control procedures were applied to all studies. Data were imputed based on the Haplotype Reference Consortium using EAGLE. Meta-analyses were performed based on GMMAT and logistic regression. The results were adjusted for sex, ancestry and PCs. PAINTOR was used to identify the plausible causal variants, and eQTL and gene enrichment analyses were performed.

We identified 16 independent significant SNPs which were specifically associated with pediatric ependymoma risk, of which 10 SNPs were plausible causal. The significant variants were located on 1q32.2 (KCNH1), 2p14 (MEIS1-AS3), 4p15.32 (LDB2), 6p21.32 (HLA-DQA), 6p21.33 (BX927178/CR759828), 7p21.3 (UMAD1), 11p12 (LRRC4C), 11q24.2 (KRT18P59), 14q24.3 (SPTLC2), and 21q11.2 (LOC112268283/FEM1AP1). The 18 identified independent significant SNPs associated with risk of adult ependymoma were located on 4p16.1 (SORCS2), 6p11.2, 6p21.31(KCTD20), 6p21.32 (HLA-DQA1), 7q31.32, 8p23.1 (LOC157273), 8q24.3 (PLEC), 10p13 (PTER), 11q23.3 (GRIK4), 19q13.11 (CEP89), and 22q11.1 (XKR3), of which 8 variants were plausible causal. One intronic variant associated with susceptibility of both pediatric and adult ependymomas was detected; rs68160486 (CCDC85A 2p16.1 PPediatric=3.41x10-8, PAdult=2.12x10-8).

The genetic architectures of adult and pediatric ependymomas appear to largely differ from one another. We identified novel variants for these tumors that have not been previously reported for GWAS of combined glioma subtypes. This analysis highlights the need to conduct additional GWAS of more refined glioma subtypes, perhaps even utilizing newer data on molecularly defined subtypes that are emerging in updated pathological classification schemes.

Citation Format: Maral Adel Fahmideh, Spiridon Tsavachidis, Stephen C. Mack, Xiao Xiangjun, Terri S. Armstrong, Mark R. Gilbert, NCI-Connect, iPSYCH Consortium, GICC, Lisa Mirabello, Smita Bhatia, Wendy M. Leisenring, Lindsay M. Morton, Gregory T. Armstrong, Jon Foss-Skiftesvik, Christian M. Hagen, Jonas Bybjerg-Grauholm, Manel Ghozal, Audrey Bonaventure, Jacqueline Clavel, Melissa L. Bondy, Christopher I. Amos, Michael E. Scheurer. Novel specific susceptibility loci identified for pediatric and adult ependymoma in first histology-specific genome-wide association study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1448.

Worldwide trends in population-based survival for children, adolescents, and young adults diagnosed with leukaemia, by subtype, during 2000-14 (CONCORD-3): analysis of individual data from 258 cancer registries in 61 countries

BACKGROUND

Leukaemias comprise a heterogenous group of haematological malignancies. In CONCORD-3, we analysed data for children (aged 0-14 years) and adults (aged 15-99 years) diagnosed with a haematological malignancy during 2000-14 in 61 countries. Here, we aimed to examine worldwide trends in survival from leukaemia, by age and morphology, in young patients (aged 0-24 years).

METHODS

We analysed data from 258 population-based cancer registries in 61 countries participating in CONCORD-3 that submitted data on patients diagnosed with leukaemia. We grouped patients by age as children (0-14 years), adolescents (15-19 years), and young adults (20-24 years). We categorised leukaemia subtypes according to the International Classification of Childhood Cancer (ICCC-3), updated with International Classification of Diseases for Oncology, third edition (ICD-O-3) codes. We estimated 5-year net survival by age and morphology, with 95% CIs, using the non-parametric Pohar-Perme estimator. To control for background mortality, we used life tables by country or region, single year of age, single calendar year and sex, and, where possible, by race or ethnicity. All-age survival estimates were standardised to the marginal distribution of young people with leukaemia included in the analysis.

FINDINGS

164 563 young people were included in this analysis: 121 328 (73·7%) children, 22 963 (14·0%) adolescents, and 20 272 (12·3%) young adults. In 2010-14, the most common subtypes were lymphoid leukaemia (28 205 [68·2%] patients) and acute myeloid leukaemia (7863 [19·0%] patients). Age-standardised 5-year net survival in children, adolescents, and young adults for all leukaemias combined during 2010-14 varied widely, ranging from 46% in Mexico to more than 85% in Canada, Cyprus, Belgium, Denmark, Finland, and Australia. Individuals with lymphoid leukaemia had better age-standardised survival (from 43% in Ecuador to ≥80% in parts of Europe, North America, Oceania, and Asia) than those with acute myeloid leukaemia (from 32% in Peru to ≥70% in most high-income countries in Europe, North America, and Oceania). Throughout 2000-14, survival from all leukaemias combined remained consistently higher for children than adolescents and young adults, and minimal improvement was seen for adolescents and young adults in most countries.

INTERPRETATION

This study offers the first worldwide picture of population-based survival from leukaemia in children, adolescents, and young adults. Adolescents and young adults diagnosed with leukaemia continue to have lower survival than children. Trends in survival from leukaemia for adolescents and young adults are important indicators of the quality of cancer management in this age group.

FUNDING

Children with Cancer UK, the Institut National du Cancer, La Ligue Contre le Cancer, Centers for Disease Control and Prevention, Swiss Re, Swiss Cancer Research foundation, Swiss Cancer League, Rossy Family Foundation, US National Cancer Institute, and the American Cancer Society.

Infant Feeding Practices And Childhood Acute Leukemia: Findings From The Childhood Cancer & Leukemia International Consortium

Increasing evidence suggests that breastfeeding may protect from childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). However, most studies have limited their analyses to any breastfeeding, and only a few data have examined exclusive breastfeeding, or other exposures such as formula milk. We performed pooled analyses and individual participant data meta-analyses of data from sixteen studies (N=17,189 controls; N=10,782 ALL and N=1,690 AML cases) from the Childhood Leukemia International Consortium (CLIC) to characterize the associations of breastfeeding duration with ALL and AML, as well as exclusive breastfeeding duration and age at introduction to formula with ALL. In unconditional multivariable logistic regression analyses of pooled data, we observed decreased odds of ALL among children breastfed 4-6 months (0.88, 95% CI 0.81-0.96) or 7-12 months (OR 0.85, 0.79-0.92). We observed a similar inverse association between breastfeeding ≥4 months and AML (0.82, 95% CI 0.71-0.95). Odds of ALL were reduced among children exclusively breastfed 4-6 months (OR 0.73, 95% CI 0.63-0.85) or 7-12 months (OR 0.70, 95% CI 0.53-0.92). Random effects meta-analyses produced similar estimates, and findings were unchanged in sensitivity analyses adjusted for race/ethnicity or mode of delivery, restricted to children diagnosed ≥1 year of age, or diagnosed with B-ALL. Our pooled analyses indicate that longer breastfeeding is associated with decreased odds of ALL and AML. Few risk factors for ALL and AML have been described, therefore our findings highlight the need to promote breastfeeding for leukemia prevention.

Excess morbidity and mortality among survivors of childhood acute lymphoblastic leukaemia: 25 years of follow-up from the United Kingdom Childhood Cancer Study (UKCCS) population-based matched cohort

OBJECTIVES

To examine morbidity and mortality among teenagers and young adults (TYAs) previously diagnosed with acute lymphoblastic leukaemia (ALL) in childhood, and compare to the general TYA population.

DESIGN

National population-based sex-matched and age-matched case-control study converted into a matched cohort, with follow-up linkage to administrative healthcare databases.

SETTING

The study population comprised all children (0-14 years) registered for primary care with the National Health Service (NHS) in England 1992-1996.

PARTICIPANTS

1082 5-year survivors of ALL diagnosed<15 years of age (1992-1996) and 2018 unaffected individuals; followed up to 15 March 2020.

MAIN OUTCOME MEASURES

Associations with hospital activity, cancer and mortality were assessed using incidence rate ratios (IRR) and differences.

RESULTS

Mortality in the 5-year ALL survivor cohort was 20 times higher than in the comparison cohort (rate ratio 21.3, 95% CI 11.2 to 45.6), and cancer incidence 10 times higher (IRR 9.9 95% CI 4.1 to 29.1). Hospital activity was increased for many clinical specialties, the strongest associations being for endocrinology; outpatient IRR 36.7, 95% CI 17.3 to 93.4 and inpatient 19.7, 95% CI 7.9 to 63.2 for males, and 11.0, 95% CI 6.2 to 21.1 and 6.2 95% CI 3.1 to 13.5, respectively, for females. Notable excesses were also evident for cardiology, neurology, ophthalmology, respiratory medicine and general medicine. Males were also more likely to attend gastroenterology; ear, nose and throat; urology; and dermatology, while females were more likely to be seen in plastic surgery and less likely in midwifery.

CONCLUSIONS

Adding to excess risks of death and cancer, survivors of childhood ALL experience excess outpatient and inpatient activity across their TYA years, which is not related to routine follow-up monitoring. Involving most clinical specialties, associations are striking, showing no signs of diminishing over time. Recognising that all survivors are potentially at risk of late treatment-associated effects, our findings underscore the need to take prior ALL diagnosis into account when interpreting seemingly unrelated symptoms later in life.

Allergies, genetic polymorphisms of Th2 interleukins, and childhood acute lymphoblastic leukemia: The ESTELLE study

CONTEXT

A negative association between a history of allergy and childhood acute lymphoblastic leukemia (ALL) has been reported in previous studies, but remains debated. This work aimed to investigate this association accounting for genetic polymorphisms of the Th2 pathway cytokines (IL4, IL10, IL13, and IL4R).

METHODS

Analyses were based on the French case-control study ESTELLE (2010-2011). The complete sample included 629 ALL cases and 1421 population-based controls frequency-matched on age and gender. The child's medical history was collected through standardized maternal interview. Biological samples were collected, and genotyping data were available for 411 cases and 704 controls of European origin. Odds ratios (OR) were estimated using unconditional regression models adjusted for potential confounders.

RESULTS

In the complete sample, a significant inverse association was observed between ALL and reported history of allergic rhinitis or sinusitis (OR = 0.65 [0.42-0.98]; P = 0.04), but there was no obvious association with allergies overall. There was an interaction between genetic polymorphisms in IL4 and IL4R (P_{interaction =} 0.003), as well as a gene-environment interaction between IL4R-rs1801275 and a reported history of asthma (IOR = 0.23; P_int  = 0.008) and eczema (IOR = 0.47; P_int  = 0.06). We observed no interaction with the candidate polymorphisms in IL4 and IL13.

CONCLUSION

These results suggest that the association between allergic symptoms and childhood ALL could be modified by IL4R-rs1801275, and that this variant could also interact with a functional variant in IL4 gene. Although they warrant confirmation, these results could help understand the pathological mechanisms under the reported inverse association between allergy and childhood ALL.

Association between multimorbidity and socioeconomic deprivation on short-term mortality among patients with diffuse large B-cell or follicular lymphoma in England: a nationwide cohort study

OBJECTIVES

We aimed to assess the association between multimorbidity and deprivation on short-term mortality among patients with diffuse large B-cell (DLBCL) and follicular lymphoma (FL) in England.

SETTING

The association of multimorbidity and socioeconomic deprivation on survival among patients diagnosed with DLBCL and FL in England between 2005 and 2013. We linked the English population-based cancer registry with electronic health records databases and estimated adjusted mortality rate ratios by multimorbidity and deprivation status. Using flexible hazard-based regression models, we computed DLBCL and FL standardised mortality risk by deprivation and multimorbidity at 1 year.

RESULTS

Overall, 41 422 patients aged 45-99 years were diagnosed with DLBCL or FL in England during 2005-2015. Most deprived patients with FL with multimorbidities had three times higher hazard of 1-year mortality (HR: 3.3, CI 2.48 to 4.28, p<0.001) than least deprived patients without comorbidity; among DLBCL, there was approximately twice the hazard (HR: 1.9, CI 1.70 to 2.07, p<0.001).

CONCLUSIONS

Multimorbidity, deprivation and their combination are strong and independent predictors of an increased short-term mortality risk among patients with DLBCL and FL in England. Public health measures targeting the reduction of multimorbidity among most deprived patients with DLBCL and FL are needed to reduce the short-term mortality gap.

Excess Mortality by Multimorbidity, Socioeconomic, and Healthcare Factors, amongst Patients Diagnosed with Diffuse Large B-Cell or Follicular Lymphoma in England

(1) Background: Socioeconomic inequalities of survival in patients with lymphoma persist, which may be explained by patients' comorbidities. We aimed to assess the association between comorbidities and the survival of patients diagnosed with diffuse large B-cell (DLBCL) or follicular lymphoma (FL) in England accounting for other socio-demographic characteristics. (2) Methods: Population-based cancer registry data were linked to Hospital Episode Statistics. We used a flexible multilevel excess hazard model to estimate excess mortality and net survival by patient's comorbidity status, adjusted for sociodemographic, economic, and healthcare factors, and accounting for the patient's area of residence. We used the latent normal joint modelling multiple imputation approach for missing data. (3) Results: Overall, 15,516 and 29,898 patients were diagnosed with FL and DLBCL in England between 2005 and 2013, respectively. Amongst DLBCL and FL patients, respectively, those in the most deprived areas showed 1.22 (95% confidence interval (CI): 1.18-1.27) and 1.45 (95% CI: 1.30-1.62) times higher excess mortality hazard compared to those in the least deprived areas, adjusted for comorbidity status, age at diagnosis, sex, ethnicity, and route to diagnosis. (4) Conclusions: Deprivation is consistently associated with poorer survival among patients diagnosed with DLBCL or FL, after adjusting for co/multimorbidities. Comorbidities and multimorbidities need to be considered when planning public health interventions targeting haematological malignancies in England.

Investigating the inequalities in route to diagnosis amongst patients with diffuse large B-cell or follicular lymphoma in England

INTRODUCTION

Diagnostic delay is associated with lower chances of cancer survival. Underlying comorbidities are known to affect the timely diagnosis of cancer. Diffuse large B-cell (DLBCL) and follicular lymphomas (FL) are primarily diagnosed amongst older patients, who are more likely to have comorbidities. Characteristics of clinical commissioning groups (CCG) are also known to impact diagnostic delay. We assess the association between comorbidities and diagnostic delay amongst patients with DLBCL or FL in England during 2005-2013.

METHODS

Multivariable generalised linear mixed-effect models were used to assess the main association. Empirical Bayes estimates of the random effects were used to explore between-cluster variation. The latent normal joint modelling multiple imputation approach was used to account for partially observed variables.

RESULTS

We included 30,078 and 15,551 patients diagnosed with DLBCL or FL, respectively. Amongst patients from the same CCG, having multimorbidity was strongly associated with the emergency route to diagnosis (DLBCL: odds ratio 1.56, CI 1.40-1.73; FL: odds ratio 1.80, CI 1.45-2.23). Amongst DLBCL patients, the diagnostic delay was possibly correlated with CCGs that had higher population densities.

CONCLUSIONS

Underlying comorbidity is associated with diagnostic delay amongst patients with DLBCL or FL. Results suggest a possible correlation between CCGs with higher population densities and diagnostic delay of aggressive lymphomas.

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.

Can we screen for pancreatic cancer? Identifying a sub-population of patients at high risk of subsequent diagnosis using machine learning techniques applied to primary care data

BACKGROUND

Pancreatic cancer (PC) represents a substantial public health burden. Pancreatic cancer patients have very low survival due to the difficulty of identifying cancers early when the tumour is localised to the site of origin and treatable. Recent progress has been made in identifying biomarkers for PC in the blood and urine, but these cannot be used for population-based screening as this would be prohibitively expensive and potentially harmful.

METHODS

We conducted a case-control study using prospectively-collected electronic health records from primary care individually-linked to cancer registrations. Our cases were comprised of 1,139 patients, aged 15-99 years, diagnosed with pancreatic cancer between January 1, 2005 and June 30, 2009. Each case was age-, sex- and diagnosis time-matched to four non-pancreatic (cancer patient) controls. Disease and prescription codes for the 24 months prior to diagnosis were used to identify 57 individual symptoms. Using a machine learning approach, we trained a logistic regression model on 75% of the data to predict patients who later developed PC and tested the model's performance on the remaining 25%.

RESULTS

We were able to identify 41.3% of patients < = 60 years at 'high risk' of developing pancreatic cancer up to 20 months prior to diagnosis with 72.5% sensitivity, 59% specificity and, 66% AUC. 43.2% of patients >60 years were similarly identified at 17 months, with 65% sensitivity, 57% specificity and, 61% AUC. We estimate that combining our algorithm with currently available biomarker tests could result in 30 older and 400 younger patients per cancer being identified as 'potential patients', and the earlier diagnosis of around 60% of tumours.

CONCLUSION

After further work this approach could be applied in the primary care setting and has the potential to be used alongside a non-invasive biomarker test to increase earlier diagnosis. This would result in a greater number of patients surviving this devastating disease.

Increased Risk of Parkinson's Disease in Women after Bilateral Oophorectomy

BACKGROUND

Results regarding the association between hormonal exposure and risk of Parkinson's disease (PD) are heterogeneous.

OBJECTIVES

To investigate the association of reproductive life characteristics with PD among postmenopausal women.

METHODS

The PARTAGE case-control included 130 female cases and 255 age-matched female controls. Information on gynecological history was obtained from a standardized questionnaire and PD was validated by neurological examination. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed using conditional logistic regression.

RESULTS

After adjustment for education level, smoking status, professional exposure to pesticides, and coffee and alcohol drinking, bilateral oophorectomy (OR = 3.55, 95%CI = 1.75-7.20), but neither menopause before age 50 years (OR = 1.24, 95%CI = 0.74-2.09) nor hormone therapy (HT; OR = 1.07, 95%CI = 0.62-1.86), was associated with PD.

CONCLUSION

Our findings suggest that bilateral oophorectomy is associated with increased risk of PD. © 2021 International Parkinson and Movement Disorder Society.

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.

Age-, sex- and disease subtype-related foetal growth differentials in childhood acute myeloid leukaemia risk: A Childhood Leukemia International Consortium analysis

AIM

Evidence for an association of foetal growth with acute myeloid leukaemia (AML) is inconclusive. AML is a rare childhood cancer, relatively more frequent in girls, with distinct features in infancy. In the context of the Childhood Leukemia International Consortium (CLIC), we examined the hypothesis that the association may vary by age, sex and disease subtype using data from 22 studies and a total of 3564 AML cases.

METHODS

Pooled estimates by age, sex and overall for harmonised foetal growth markers in association with AML were calculated using the International Fetal and Newborn Growth Consortium for the 21st Century Project for 17 studies contributing individual-level data; meta-analyses were, thereafter, conducted with estimates provided ad hoc by five more studies because of administrative constraints. Subanalyses by AML subtype were also performed.

RESULTS

A nearly 50% increased risk was observed among large-for-gestational-age infant boys (odds ratio [OR]: 1.49, 95% confidence interval [CI]: 1.03-2.14), reduced to 34% in boys aged <2 years (OR: 1.34, 95% CI: 1.05-1.71) and 25% in boys aged 0-14 years (OR: 1.25, 95% CI: 1.06-1.46). The association of large for gestational age became stronger in boys with M0/M1subtype (OR: 1.80, 95% CI: 1.15-2.83). Large birth length for gestational age was also positively associated with AML (OR: 1.38, 95% CI: 1.00-1.92) in boys. By contrast, there were null associations in girls, as well as with respect to associations of decelerated foetal growth markers.

CONCLUSIONS

Accelerated foetal growth was associated with AML, especially in infant boys and those with minimally differentiated leukaemia. Further cytogenetic research would shed light into the underlying mechanisms.

Paediatric acute lymphoblastic leukaemia and caesarean section: A report from the United Kingdom Childhood Cancer Study (UKCCS)

BACKGROUND

Reports have suggested that children born by caesarean initiated before labour onset may be at increased risk of developing acute lymphoblastic leukaemia (ALL). However, with most data being derived from case-control study interviews, information on the underpinning reasons for caesarean section is sparse, and evidence is conflicting.

OBJECTIVES

Use clinical records compiled at the time of delivery to investigate the association between childhood ALL and caesarean delivery; examining timing in relation to labour onset, and reasons for the procedure.

METHODS

Data are from the UK Childhood Cancer Study, a population-based case-control study conducted in the 1990s, when caesarean section rates were relatively low, in England, Scotland, and Wales. Children with ALL were individually matched to two controls on sex, date of birth, and region of residence. Information on mode of delivery and complications was abstracted from obstetric records. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression models adjusted for matching variables and relevant covariates.

RESULTS

Around 75% of the 1034 cases and 1914 controls were born through unassisted vaginal delivery. Caesarean delivery was as frequent in cases and controls (OR 1.07, 95% CI 0.84, 1.36). No association was observed between ALL and caesarean delivery either during or before labour, with adjusted ORs of 1.08 (95% CI 0.78, 1.48) and 1.09 (95% CI 0.78, 1.53), respectively. For B-cell ALL, the ORs were 1.14 (95% CI 0.81, 1.59) for caesarean during labour and 1.21 (95% CI 0.85, 1.72) for prelabour. The underpinning reasons for caesarean delivery differed between cases and controls; with preeclampsia, although very rare, being more common amongst cases born by caesarean (OR 8.91, 95% CI 1.48, 53.42).

CONCLUSIONS

Our obstetric record-based study found no significant evidence that caesarean delivery increased the risk of childhood ALL, either overall or when carried out before labour.

Racial/ethnic and socioeconomic survival disparities for children and adolescents with central nervous system tumours in the United States, 2000-2015

BACKGROUND AND OBJECTIVES

Central nervous system (CNS) malignancy is the commonest cause of cancer death in children and adolescents (0-19 years) in high-income settings. There is limited data on survival inequalities by race/ethnicity and socioeconomic position (SEP), for young patients, we aim to analyse their influence on survival from childhood CNS tumour.

METHODS

9577 children and adolescents diagnosed with primary malignant CNS tumours during 2000-2015, followed up until Dec 31 st, 2015, and reported to cancer registries (Surveillance, Epidemiology and End Results programme) were included in the analysis. Cox regression models estimated the hazard ratios for race/ethnicity, SEP, and individual insurance status, adjusting for sex, age, diagnostic period, and tumour type. Individual-level insurance status data were available from 2007.

RESULTS

62.5 % children and adolescents were non-Hispanic White, 10.6 % were non-Hispanic Black and 26.9 % were Hispanic. Race/ethnicity was strongly associated with survival (p < 0.001), even after adjusting for SEP, with Black (HR = 1.39 [95 %CI 1.23-1.58]) and Hispanic children (HR = 1.40 [95 %CI 1.28-1.54]) having higher hazards of death than White children. This association remained after adjusting for insurance status. There was an apparent positive association between SEP and survival that was largely attenuated after adjustment for insurance status (p = 0.20). Survival was comparable between those privately and Medicaid-insured.

CONCLUSIONS

Non-Hispanic Black and Hispanic children had lower survival than their White counterparts. This association, not fully explained by differences in SEP, tumour subtype or health insurance, could be related to racially/ethnically-driven barriers to optimal healthcare, warranting further investigation.

Coffee and tea consumption during pregnancy and risk of childhood acute myeloid leukemia: A Childhood Leukemia International Consortium (CLIC) study

BACKGROUND

Dietary habits during pregnancy have been inconsistently linked to childhood acute myeloid leukemia (AML), given the putative intrauterine onset of the disease as a result of triggering events during the critical period of fetal hematopoiesis. We investigated the potential association of maternal coffee and tea consumption during pregnancy with childhood AML risk, pooling primary data from eight case-control studies participating in the Childhood Leukemia International Consortium.

METHODS

Information on coffee and/or tea consumption was available for 444 cases and 1255 age- and sex-matched controls, on coffee consumption for 318 cases and 971 controls and on tea consumption for 388 cases and 932 controls. Categories for cups of daily coffee/tea consumption were created in order to explore potential dose-response associations. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression.

RESULTS

Associations were found neither in the analysis on coffee or tea nor in the analysis on coffee only consumption (any versus no). A positive association with increasing coffee intake was observed (>1 cup per day; OR: 1.40, 95% CI: 1.03-1.92, increment of one cup per day; OR: 1.18, 95% CI: 1.01-1.39). No associations were observed with tea consumption. Interaction analyses showed non-significant associations between coffee/tea and smoking. Hyperdiploidy was inversely associated with tea consumption, with other cytogenetic markers having no association with coffee/tea.

CONCLUSION

Given the widespread consumption of caffeinated beverages among pregnant women, our finding is of important public health relevance, suggesting adverse effects of maternal coffee consumption during pregnancy in the offspring.

Temporal trends in the proportion of "cure" in children, adolescents, and young adults diagnosed with chronic myeloid leukemia in England: A population-based study

BACKGROUND

Survival probability in children, adolescents, and young adults with chronic myeloid leukemia (CML) has dramatically improved during recent years. Tyrosine kinase inhibitors (TKI), targeted drugs developed for patients with CML, were introduced in 2001 in England. We here quantify the trends in the "cure" proportion according to the year of diagnosis.

METHODS

We included all children, adolescents, and young patients with CML (0 to 24 years) diagnosed in England during 1980 to 2005. We fitted mixture cure models to estimate the "cure" proportion and the median survival time among the "uncured" patients according to the year of diagnosis, adjusted for age at diagnosis.

RESULTS

The "cure" proportion increased dramatically between 1980 and 2005, from under 10% to over 80%, while conversely, the median survival time of "uncured" patients decreased slightly between 1980 and 1999, with the trend from 2000 being uncertain.

CONCLUSIONS

The striking improvement of the "cure" fraction in young patients with CML since the early 1980s is concomitant with improvement of treatment, especially the allogeneic hematopoietic stem-cell transplant and, later, the introduction of TKI. The trends over the last years (2000-2005) remain, however, uncertain and would benefit from further studies with more recent data and updated follow-up.

Adult leukemia survival trends in the United States by subtype: A population-based registry study of 370,994 patients diagnosed during 1995-2009

BACKGROUND

The lifetime risk of developing leukemia in the United States is 1.5%. There are challenges in the estimation of population-based survival using registry data because treatments and prognosis vary greatly by subtype. The objective of the current study was to determine leukemia survival estimates in the United States from 1995 to 2009 according to subtype, sex, geographical area, and race.

METHODS

Five-year net survival was estimated using data for 370,994 patients from 43 registries in 37 states and in 6 metropolitan areas, covering approximately 81% of the adult (15-99 years) US population. Leukemia was categorized according to principal subtype (chronic lymphocytic leukemia, acute myeloid leukemia, and acute lymphocytic leukemia), and subcategorized in accordance with the HAEMACARE protocol. We analyzed age-standardized 5-year net survival by calendar period (1995-1999, 2000-2004, and 2005-2009), leukemia subtype, sex, race, and US state.

RESULTS

The age-standardized 5-year net survival estimates increased from 45.0% for patients diagnosed during 1995-1999 to 49.0% for those diagnosed during 2000-2004 and 52.0% for those diagnosed during 2005-2009. For patients diagnosed during 2005-2009, 5-year survival was 18.2% (95% confidence interval [95% CI], 17.8%-18.6%) for acute myeloid leukemia, 44.0% (95% CI, 43.2%-44.8%) for acute lymphocytic leukemia, and 77.3% (95% CI, 76.9%-77.7%) for chronic lymphocytic leukemia. For nearly all leukemia subtypes, survival declined in successive age groups above 45 to 54 years. Men were found to have slightly lower survival than women; however, this discrepancy was noted to have fallen in successive calendar periods. Net survival was substantially higher in white than black patients in all calendar periods. There were large differences in survival noted between states and metropolitan areas.

CONCLUSIONS

Survival from leukemia in US adults improved during 1995-2009. Some geographical differences in survival may be related to access to care. We found disparities in survival by sex and between black and white patients.

Genetic polymorphisms of Th2 interleukins, history of asthma or eczema and childhood acute lymphoid leukaemia: Findings from the ESCALE study (SFCE)

BACKGROUND

Previous studies on the putative role of allergy in the aetiology of childhood leukaemia have reported contradictory results. The present study aimed to analyse the relation between a medical history of asthma or eczema and childhood acute lymphoid leukaemia (ALL) in light of potential candidate gene-environment interactions.

METHODS

Analyses were based on a subset of 434 cases of ALL and 442 controls successfully genotyped and of European ancestry children enrolled in a French population-based case-control study conducted in 2003-2004. Information about medical history was obtained during a standardized interview with the mothers. Candidate polymorphisms in genes of the Th2 cytokines IL4, IL10, IL13 and IL4-receptor, were genotyped or imputed.

RESULTS

None of the variant alleles were directly associated with childhood acute lymphoid leukaemia. A medical history of asthma or eczema was reported more often in the control group (OR = 0.7 [0.5-1.0]). This association was mostly seen in the group of children not carrying the IL13-rs20541 variant allele (Interaction Odds Ratio IOR 1.9, p-interaction = 0.07) and in those carrying the IL10 triple variant haplotype (IOR 0.5, p-interaction = 0.04). No interaction was observed with the candidate polymorphisms in IL4 and IL4R.

CONCLUSION

This study provides a new insight into the relationship between allergic symptoms and childhood acute lymphoid leukaemia, by suggesting this inverse association could be limited to children carrying certain genetic polymorphisms. If confirmed, these results could help better understand the biological mechanisms involved in the development of childhood acute lymphoid leukaemia.

Global surveillance of trends in cancer survival 2000-14 (CONCORD-3): analysis of individual records for 37 513 025 patients diagnosed with one of 18 cancers from 322 population-based registries in 71 countries

BACKGROUND

In 2015, the second cycle of the CONCORD programme established global surveillance of cancer survival as a metric of the effectiveness of health systems and to inform global policy on cancer control. CONCORD-3 updates the worldwide surveillance of cancer survival to 2014.

METHODS

CONCORD-3 includes individual records for 37·5 million patients diagnosed with cancer during the 15-year period 2000-14. Data were provided by 322 population-based cancer registries in 71 countries and territories, 47 of which provided data with 100% population coverage. The study includes 18 cancers or groups of cancers: oesophagus, stomach, colon, rectum, liver, pancreas, lung, breast (women), cervix, ovary, prostate, and melanoma of the skin in adults, and brain tumours, leukaemias, and lymphomas in both adults and children. Standardised quality control procedures were applied; errors were rectified by the registry concerned. We estimated 5-year net survival. Estimates were age-standardised with the International Cancer Survival Standard weights.

FINDINGS

For most cancers, 5-year net survival remains among the highest in the world in the USA and Canada, in Australia and New Zealand, and in Finland, Iceland, Norway, and Sweden. For many cancers, Denmark is closing the survival gap with the other Nordic countries. Survival trends are generally increasing, even for some of the more lethal cancers: in some countries, survival has increased by up to 5% for cancers of the liver, pancreas, and lung. For women diagnosed during 2010-14, 5-year survival for breast cancer is now 89·5% in Australia and 90·2% in the USA, but international differences remain very wide, with levels as low as 66·1% in India. For gastrointestinal cancers, the highest levels of 5-year survival are seen in southeast Asia: in South Korea for cancers of the stomach (68·9%), colon (71·8%), and rectum (71·1%); in Japan for oesophageal cancer (36·0%); and in Taiwan for liver cancer (27·9%). By contrast, in the same world region, survival is generally lower than elsewhere for melanoma of the skin (59·9% in South Korea, 52·1% in Taiwan, and 49·6% in China), and for both lymphoid malignancies (52·5%, 50·5%, and 38·3%) and myeloid malignancies (45·9%, 33·4%, and 24·8%). For children diagnosed during 2010-14, 5-year survival for acute lymphoblastic leukaemia ranged from 49·8% in Ecuador to 95·2% in Finland. 5-year survival from brain tumours in children is higher than for adults but the global range is very wide (from 28·9% in Brazil to nearly 80% in Sweden and Denmark).

INTERPRETATION

The CONCORD programme enables timely comparisons of the overall effectiveness of health systems in providing care for 18 cancers that collectively represent 75% of all cancers diagnosed worldwide every year. It contributes to the evidence base for global policy on cancer control. Since 2017, the Organisation for Economic Co-operation and Development has used findings from the CONCORD programme as the official benchmark of cancer survival, among their indicators of the quality of health care in 48 countries worldwide. Governments must recognise population-based cancer registries as key policy tools that can be used to evaluate both the impact of cancer prevention strategies and the effectiveness of health systems for all patients diagnosed with cancer.

FUNDING

American Cancer Society; Centers for Disease Control and Prevention; Swiss Re; Swiss Cancer Research foundation; Swiss Cancer League; Institut National du Cancer; La Ligue Contre le Cancer; Rossy Family Foundation; US National Cancer Institute; and the Susan G Komen Foundation.

Childhood cancer incidence and survival in Japan and England: A population-based study (1993-2010)

The present study aimed to compare cancer incidence and trends in survival for children diagnosed in Japan and England, using population-based cancer registry data. The analysis was based on 5192 children with cancer (age 0-14 years) from 6 prefectural cancer registries in Japan and 21 295 children diagnosed in England during 1993-2010. Differences in incidence rates between the 2 countries were measured with Poisson regression models. Overall survival was estimated using the Kaplan-Meier method. Incidence rates for Hodgkin lymphoma, renal tumors and Ewing sarcomas in England were more than twice as high as those in Japan. Incidence of germ cell tumors, hepatic tumors, neuroblastoma and acute myeloid leukemia (AML) was higher in Japan than in England. Incidence of all cancers combined decreased in Japan throughout the period 1993 to 2010, which was mainly explained by a decrease in registration of neuroblastoma in infants. For many cancers, 5-year survival improved in both countries. The improvement in survival in chronic myeloid leukemia (CML) was particularly dramatic in both countries. However, 5-year survival remained less than 80% in 2005-2008 in both countries for AML, brain tumors, soft tissue sarcomas, malignant bone tumors and neuroblastoma (age 1-14 years). There were significant differences in incidence of several cancers between countries, suggesting variation in genetic susceptibility and possibly environmental factors. The decrease in incidence for all cancers combined in Japan was related to the cessation of the national screening program for neuroblastoma. The large improvement in survival in CML coincided with the introduction of effective therapy (imatinib).

Survival among children diagnosed with acute lymphoblastic leukemia in the United States, by race and age, 2001 to 2009: Findings from the CONCORD-2 study

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. This report describes the survival of children with ALL in the United States using the most comprehensive and up-to-date cancer registry data.

METHODS

Data from 37 state cancer registries that cover approximately 80% of the US population were used. Age-standardized survival up to 5 years was estimated for children aged 0-14 years who were diagnosed with ALL during 2 periods (2001-2003 and 2004-2009).

RESULTS

In total, 17,500 children with ALL were included. The pooled age-standardized net survival estimates for all US registries combined were 95% at 1 year, 90% at 3 years, and 86% at 5 years for children diagnosed during 2001-2003, and 96%, 91%, and 88%, respectively, for those diagnosed during 2004-2009. Black children who were diagnosed during 2001-2003 had lower 5-year survival (84%) than white children (87%) and had less improvement in survival by 2004-2009. For those diagnosed during 2004-2009, the 1-year and 5-year survival estimates were 96% and 89%, respectively, for white children and 96% and 84%, respectively, for black children. During 2004-2009, survival was highest among children aged 1 to 4 years (95%) and lowest among children aged <1 year (60%).

CONCLUSIONS

The current results indicate that overall net survival from childhood ALL in the United States is high, but disparities by race still exist, especially beyond the first year after diagnosis. Clinical and public health strategies are needed to improve health care access, clinical trial enrollment, treatment, and survivorship care for children with ALL. Cancer 2017;123:5178-89. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Population-based cancer survival in the United States: Data, quality control, and statistical methods

BACKGROUND

Robust comparisons of population-based cancer survival estimates require tight adherence to the study protocol, standardized quality control, appropriate life tables of background mortality, and centralized analysis. The CONCORD program established worldwide surveillance of population-based cancer survival in 2015, analyzing individual data on 26 million patients (including 10 million US patients) diagnosed between 1995 and 2009 with 1 of 10 common malignancies.

METHODS

In this Cancer supplement, we analyzed data from 37 state cancer registries that participated in the second cycle of the CONCORD program (CONCORD-2), covering approximately 80% of the US population. Data quality checks were performed in 3 consecutive phases: protocol adherence, exclusions, and editorial checks. One-, 3-, and 5-year age-standardized net survival was estimated using the Pohar Perme estimator and state- and race-specific life tables of all-cause mortality for each year. The cohort approach was adopted for patients diagnosed between 2001 and 2003, and the complete approach for patients diagnosed between 2004 and 2009.

RESULTS

Articles in this supplement report population coverage, data quality indicators, and age-standardized 5-year net survival by state, race, and stage at diagnosis. Examples of tables, bar charts, and funnel plots are provided in this article.

CONCLUSIONS

Population-based cancer survival is a key measure of the overall effectiveness of services in providing equitable health care. The high quality of US cancer registry data, 80% population coverage, and use of an unbiased net survival estimator ensure that the survival trends reported in this supplement are robustly comparable by race and state. The results can be used by policymakers to identify and address inequities in cancer survival in each state and for the United States nationally. Cancer 2017;123:4982-93. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Worldwide comparison of survival from childhood leukaemia for 1995-2009, by subtype, age, and sex (CONCORD-2): a population-based study of individual data for 89 828 children from 198 registries in 53 countries

BACKGROUND

Global inequalities in access to health care are reflected in differences in cancer survival. The CONCORD programme was designed to assess worldwide differences and trends in population-based cancer survival. In this population-based study, we aimed to estimate survival inequalities globally for several subtypes of childhood leukaemia.

METHODS

Cancer registries participating in CONCORD were asked to submit tumour registrations for all children aged 0-14 years who were diagnosed with leukaemia between Jan 1, 1995, and Dec 31, 2009, and followed up until Dec 31, 2009. Haematological malignancies were defined by morphology codes in the International Classification of Diseases for Oncology, third revision. We excluded data from registries from which the data were judged to be less reliable, or included only lymphomas, and data from countries in which data for fewer than ten children were available for analysis. We also excluded records because of a missing date of birth, diagnosis, or last known vital status. We estimated 5-year net survival (ie, the probability of surviving at least 5 years after diagnosis, after controlling for deaths from other causes [background mortality]) for children by calendar period of diagnosis (1995-99, 2000-04, and 2005-09), sex, and age at diagnosis (<1, 1-4, 5-9, and 10-14 years, inclusive) using appropriate life tables. We estimated age-standardised net survival for international comparison of survival trends for precursor-cell acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML).

FINDINGS

We analysed data from 89 828 children from 198 registries in 53 countries. During 1995-99, 5-year age-standardised net survival for all lymphoid leukaemias combined ranged from 10·6% (95% CI 3·1-18·2) in the Chinese registries to 86·8% (81·6-92·0) in Austria. International differences in 5-year survival for childhood leukaemia were still large as recently as 2005-09, when age-standardised survival for lymphoid leukaemias ranged from 52·4% (95% CI 42·8-61·9) in Cali, Colombia, to 91·6% (89·5-93·6) in the German registries, and for AML ranged from 33·3% (18·9-47·7) in Bulgaria to 78·2% (72·0-84·3) in German registries. Survival from precursor-cell ALL was very close to that of all lymphoid leukaemias combined, with similar variation. In most countries, survival from AML improved more than survival from ALL between 2000-04 and 2005-09. Survival for each type of leukaemia varied markedly with age: survival was highest for children aged 1-4 and 5-9 years, and lowest for infants (younger than 1 year). There was no systematic difference in survival between boys and girls.

INTERPRETATION

Global inequalities in survival from childhood leukaemia have narrowed with time but remain very wide for both ALL and AML. These results provide useful information for health policy makers on the effectiveness of health-care systems and for cancer policy makers to reduce inequalities in childhood cancer survival.

FUNDING

Canadian Partnership Against Cancer, Cancer Focus Northern Ireland, Cancer Institute New South Wales, Cancer Research UK, US Centers for Disease Control and Prevention, Swiss Re, Swiss Cancer Research foundation, Swiss Cancer League, and the University of Kentucky.

Life tables for global surveillance of cancer survival (the CONCORD programme): data sources and methods

BACKGROUND

We set out to estimate net survival trends for 10 common cancers in 279 cancer registry populations in 67 countries around the world, as part of the CONCORD-2 study. Net survival can be interpreted as the proportion of cancer patients who survive up to a given time, after eliminating the impact of mortality from other causes (background mortality). Background mortality varies widely between populations and over time. It was therefore necessary to construct robust life tables that accurately reflected the background mortality in each of the registry populations.

METHODS

Life tables of all-cause mortality rates by single year of age and sex were constructed by calendar year for each population and, when possible, by racial or ethnic sub-groups. We used three different approaches, based on the type of mortality data available from each registry. With death and population counts, we adopted a flexible multivariable modelling approach. With unsmoothed mortality rates, we used the Ewbank relational method. Where no data were available from the registry or a national statistical office, we used the abridged UN Population Division life tables and interpolated these using the Elandt-Johnson method. We also investigated the impact of using state- and race-specific life tables versus national race-specific life tables on estimates of net survival from four adult cancers in the United States (US).

RESULTS

We constructed 6,514 life tables covering 327 populations. Wide variations in life expectancy at birth and mortality by age were observed, even within countries. During 1995-99, life expectancy was lowest in Nigeria and highest in Japan, ranging from 47 to 84 years among females and 46 to 78 years among males. During 2005-09, life expectancy was lowest in Lesotho and again highest in Japan, ranging from 45 to 86 years among females and 45 to 80 years among males. For the US, estimates of net survival differed by up to 4% if background mortality was fully controlled with state- and race-specific life tables, rather than with national race-specific life tables.

CONCLUSIONS

Background mortality varies worldwide. This emphasises the importance of using population-specific life tables for geographic and international comparisons of net survival.

ARID5B, IKZF1 and non-genetic factors in the etiology of childhood acute lymphoblastic leukemia: the ESCALE study

Genome-wide association studies (GWAS) have identified that frequent polymorphisms in ARID5B and IKZF1, two genes involved in lymphoid differentiation, increase the risk of childhood acute lymphoblastic leukemia (ALL). These findings markedly modified the current field of research on the etiology of ALL. In this new context, the present exploratory study investigated the possible interactions between these at-risk alleles and the non-genetic suspected ALL risk factors that were of sufficient prevalence in the French ESCALE study: maternal use of home insecticides during pregnancy, preconception paternal smoking, and some proxies for early immune modulation, i.e. breastfeeding, history of common infections before age one year, and birth order. The analyses were based on 434 ALL cases and 442 controls of European origin, drawn from the nationwide population-based case-control study ESCALE. Information on non-genetic factors was obtained by standardized telephone interview. Interactions between rs10740055 in ARID5B or rs4132601 in IKZF1 and each of the suspected non-genetic factors were tested, with the SNPs coded as counts of minor alleles (trend variable). Statistical interactions were observed between rs4132601 and maternal insecticide use (p = 0.012), breastfeeding p = 0.017) and repeated early common infections (p = 0.0070), with allelic odds ratios (OR) which were only increased among the children not exposed to insecticides (OR = 1.8, 95%CI: 1.3, 2.4), those who had been breastfed (OR = 1.8, 95%CI: 1.3, 2.5) and those who had had repeated early common infections (OR = 2.4, 95%CI: 1.5, 3.8). The allelic ORs were close to one among children exposed to insecticides, who had not been breastfed and who had had no or few common infections. Repeated early common infections interacted with rs10740055 (p = 0.018) in the case-only design. Further studies are needed to evaluate whether these observations of a modification of the effect of the at-risk alleles by non-genetic factors are chance findings or reflect true underlying mechanisms.

Global surveillance of cancer survival 1995-2009: analysis of individual data for 25,676,887 patients from 279 population-based registries in 67 countries (CONCORD-2)

BACKGROUND

Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control.

METHODS

Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights.

FINDINGS

5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease.

INTERPRETATION

International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems.

FUNDING

Canadian Partnership Against Cancer (Toronto, Canada), Cancer Focus Northern Ireland (Belfast, UK), Cancer Institute New South Wales (Sydney, Australia), Cancer Research UK (London, UK), Centers for Disease Control and Prevention (Atlanta, GA, USA), Swiss Re (London, UK), Swiss Cancer Research foundation (Bern, Switzerland), Swiss Cancer League (Bern, Switzerland), and University of Kentucky (Lexington, KY, USA).

Years lived with disability (YLDs) for 1160 sequelae of 289 diseases and injuries 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010

BACKGROUND

Non-fatal health outcomes from diseases and injuries are a crucial consideration in the promotion and monitoring of individual and population health. The Global Burden of Disease (GBD) studies done in 1990 and 2000 have been the only studies to quantify non-fatal health outcomes across an exhaustive set of disorders at the global and regional level. Neither effort quantified uncertainty in prevalence or years lived with disability (YLDs).

METHODS

Of the 291 diseases and injuries in the GBD cause list, 289 cause disability. For 1160 sequelae of the 289 diseases and injuries, we undertook a systematic analysis of prevalence, incidence, remission, duration, and excess mortality. Sources included published studies, case notification, population-based cancer registries, other disease registries, antenatal clinic serosurveillance, hospital discharge data, ambulatory care data, household surveys, other surveys, and cohort studies. For most sequelae, we used a Bayesian meta-regression method, DisMod-MR, designed to address key limitations in descriptive epidemiological data, including missing data, inconsistency, and large methodological variation between data sources. For some disorders, we used natural history models, geospatial models, back-calculation models (models calculating incidence from population mortality rates and case fatality), or registration completeness models (models adjusting for incomplete registration with health-system access and other covariates). Disability weights for 220 unique health states were used to capture the severity of health loss. YLDs by cause at age, sex, country, and year levels were adjusted for comorbidity with simulation methods. We included uncertainty estimates at all stages of the analysis.

FINDINGS

Global prevalence for all ages combined in 2010 across the 1160 sequelae ranged from fewer than one case per 1 million people to 350,000 cases per 1 million people. Prevalence and severity of health loss were weakly correlated (correlation coefficient -0·37). In 2010, there were 777 million YLDs from all causes, up from 583 million in 1990. The main contributors to global YLDs were mental and behavioural disorders, musculoskeletal disorders, and diabetes or endocrine diseases. The leading specific causes of YLDs were much the same in 2010 as they were in 1990: low back pain, major depressive disorder, iron-deficiency anaemia, neck pain, chronic obstructive pulmonary disease, anxiety disorders, migraine, diabetes, and falls. Age-specific prevalence of YLDs increased with age in all regions and has decreased slightly from 1990 to 2010. Regional patterns of the leading causes of YLDs were more similar compared with years of life lost due to premature mortality. Neglected tropical diseases, HIV/AIDS, tuberculosis, malaria, and anaemia were important causes of YLDs in sub-Saharan Africa.

INTERPRETATION

Rates of YLDs per 100,000 people have remained largely constant over time but rise steadily with age. Population growth and ageing have increased YLD numbers and crude rates over the past two decades. Prevalences of the most common causes of YLDs, such as mental and behavioural disorders and musculoskeletal disorders, have not decreased. Health systems will need to address the needs of the rising numbers of individuals with a range of disorders that largely cause disability but not mortality. Quantification of the burden of non-fatal health outcomes will be crucial to understand how well health systems are responding to these challenges. Effective and affordable strategies to deal with this rising burden are an urgent priority for health systems in most parts of the world.

FUNDING

Bill & Melinda Gates Foundation.

Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010

BACKGROUND

Measuring disease and injury burden in populations requires a composite metric that captures both premature mortality and the prevalence and severity of ill-health. The 1990 Global Burden of Disease study proposed disability-adjusted life years (DALYs) to measure disease burden. No comprehensive update of disease burden worldwide incorporating a systematic reassessment of disease and injury-specific epidemiology has been done since the 1990 study. We aimed to calculate disease burden worldwide and for 21 regions for 1990, 2005, and 2010 with methods to enable meaningful comparisons over time.

METHODS

We calculated DALYs as the sum of years of life lost (YLLs) and years lived with disability (YLDs). DALYs were calculated for 291 causes, 20 age groups, both sexes, and for 187 countries, and aggregated to regional and global estimates of disease burden for three points in time with strictly comparable definitions and methods. YLLs were calculated from age-sex-country-time-specific estimates of mortality by cause, with death by standardised lost life expectancy at each age. YLDs were calculated as prevalence of 1160 disabling sequelae, by age, sex, and cause, and weighted by new disability weights for each health state. Neither YLLs nor YLDs were age-weighted or discounted. Uncertainty around cause-specific DALYs was calculated incorporating uncertainty in levels of all-cause mortality, cause-specific mortality, prevalence, and disability weights.

FINDINGS

Global DALYs remained stable from 1990 (2·503 billion) to 2010 (2·490 billion). Crude DALYs per 1000 decreased by 23% (472 per 1000 to 361 per 1000). An important shift has occurred in DALY composition with the contribution of deaths and disability among children (younger than 5 years of age) declining from 41% of global DALYs in 1990 to 25% in 2010. YLLs typically account for about half of disease burden in more developed regions (high-income Asia Pacific, western Europe, high-income North America, and Australasia), rising to over 80% of DALYs in sub-Saharan Africa. In 1990, 47% of DALYs worldwide were from communicable, maternal, neonatal, and nutritional disorders, 43% from non-communicable diseases, and 10% from injuries. By 2010, this had shifted to 35%, 54%, and 11%, respectively. Ischaemic heart disease was the leading cause of DALYs worldwide in 2010 (up from fourth rank in 1990, increasing by 29%), followed by lower respiratory infections (top rank in 1990; 44% decline in DALYs), stroke (fifth in 1990; 19% increase), diarrhoeal diseases (second in 1990; 51% decrease), and HIV/AIDS (33rd in 1990; 351% increase). Major depressive disorder increased from 15th to 11th rank (37% increase) and road injury from 12th to 10th rank (34% increase). Substantial heterogeneity exists in rankings of leading causes of disease burden among regions.

INTERPRETATION

Global disease burden has continued to shift away from communicable to non-communicable diseases and from premature death to years lived with disability. In sub-Saharan Africa, however, many communicable, maternal, neonatal, and nutritional disorders remain the dominant causes of disease burden. The rising burden from mental and behavioural disorders, musculoskeletal disorders, and diabetes will impose new challenges on health systems. Regional heterogeneity highlights the importance of understanding local burden of disease and setting goals and targets for the post-2015 agenda taking such patterns into account. Because of improved definitions, methods, and data, these results for 1990 and 2010 supersede all previously published Global Burden of Disease results.

FUNDING

Bill & Melinda Gates Foundation.

Impact of recommendations on the initial therapy of Parkinson's disease: a population-based study in France

Levodopa induces long-term motor complications in Parkinson's disease (PD). Therapeutic strategies that prevent motor complications are needed. Our aim was to evaluate the impact of recommendations of a French consensus conference published in 2000 on initial PD therapy. We identified 308 PD patients as part of a population-based study performed within the Mutualité Sociale Agricole in five French districts (2007). Neurologists confirmed PD diagnosis. We compared initial therapy in 102 patients treated before 12/31/2000 to that of 206 patients treated afterwards. Initial treatment was in agreement with the recommendations if dopamine agonists were used in patients <60 years (n = 49) and levodopa in patients ≥70 years (n = 133). Agreement with the recommendations increased after 2000 (66.0%) compared to before (46.3%, p = 0.025). For patients <60 years, agreement increased (64.0% vs 20.2%, p = 0.017) while it remained stable (66.4% vs 70.6%, p = 0.73) in patients ≥70 years. The publication of recommendations has influenced initial treatment choices for PD in France.

Triglycerides and risk of hemorrhagic stroke vs. ischemic vascular events: The Three-City Study

BACKGROUND

Few studies have assessed the relationship between triglycerides and the risk of hemorrhagic stroke, which contrasts the considerable number of studies about triglycerides and ischemic vascular events. We analyzed the association pattern between triglycerides and incident intracerebral hemorrhage as compared with coronary events and ischemic stroke, in a large cohort of elderly.

METHODS

Population-based, prospective cohort study among 8393 men and women participating in the Three-City Study, aged > or = 65 years at baseline. Fasting blood lipids, including triglycerides, were measured at baseline. Fatal and non-fatal strokes and coronary events were adjudicated and validated by scientific committees. Cox proportional hazards models were used to adjust for potential confounders.

RESULTS

During a mean follow-up of 5.0 years, 36 hemorrhagic strokes, 143 ischemic strokes, and 393 coronary events occurred. An increased level of triglycerides was associated with an increased risk of ischemic vascular events. Conversely, a low level of triglycerides (< or = 0.94 mmol/L) was associated with an increased risk of hemorrhagic stroke (adjusted hazard ratio 2.35; 95% confidence interval 1.18-4.70). The relationship with hemorrhagic stroke was mainly apparent in men, in individuals with high blood pressure, and in those with low levels of cholesterol.

CONCLUSIONS

In this large cohort of elderly men and women, low triglycerides levels were associated with an increased risk of hemorrhagic stroke and a decreased risk of ischemic vascular events. The association between triglycerides and hemorrhagic stroke was particularly strong in men, in subjects with high blood pressure and in those with low cholesterol levels.