Shifting incidence and survival of epithelial ovarian cancer (1995-2014): A SurvMark-2 study.

The aim of the study is to provide a comprehensive assessment of incidence and survival trends of epithelial ovarian cancer (EOC) by histological subtype across seven high income countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway and the United Kingdom). Data on invasive EOC diagnosed in women aged 15 to 99 years during 1995 to 2014 were obtained from 20 cancer registries. Age standardized incidence rates and average annual percentage change were calculated by subtype for all ages and age groups (15-64 and 65-99 years). Net survival (NS) was estimated by subtype, age group and 5-year period using Pohar-Perme estimator. Our findings showed marked increase in serous carcinoma incidence was observed between 1995 and 2014 among women aged 65 to 99 years with average annual increase ranging between 2.2% and 5.8%. We documented a marked decrease in the incidence of adenocarcinoma "not otherwise specified" with estimates ranging between 4.4% and 7.4% in women aged 15 to 64 years and between 2.0% and 3.7% among the older age group. Improved survival, combining all EOC subtypes, was observed for all ages combined over the 20-year study period in all countries with 5-year NS absolute percent change ranging between 5.0 in Canada and 12.6 in Denmark. Several factors such as changes in guidelines and advancement in diagnostic tools may potentially influence the observed shift in histological subtypes and temporal trends. Progress in clinical management and treatment over the past decades potentially plays a role in the observed improvements in EOC survival.

Global survival trends for brain tumors, by histology: analysis of individual records for 556,237 adults diagnosed in 59 countries during 2000-2014 (CONCORD-3).

BACKGROUND: Survival is a key metric of the effectiveness of a health system in managing cancer. We set out to provide a comprehensive examination of worldwide variation and trends in survival from brain tumors in adults, by histology. METHODS: We analyzed individual data for adults (15-99 years) diagnosed with a brain tumor (ICD-O-3 topography code C71) during 2000-2014, regardless of tumor behavior. Data underwent a 3-phase quality control as part of CONCORD-3. We estimated net survival for 11 histology groups, using the unbiased nonparametric Pohar Perme estimator. RESULTS: The study included 556,237 adults. In 2010-2014, the global range in age-standardized 5-year net survival for the most common sub-types was broad: in the range 20%-38% for diffuse and anaplastic astrocytoma, from 4% to 17% for glioblastoma, and between 32% and 69% for oligodendroglioma. For patients with glioblastoma, the largest gains in survival occurred between 2000-2004 and 2005-2009. These improvements were more noticeable among adults diagnosed aged 40-70 years than among younger adults. CONCLUSIONS: To the best of our knowledge, this study provides the largest account to date of global trends in population-based survival for brain tumors by histology in adults. We have highlighted remarkable gains in 5-year survival from glioblastoma since 2005, providing large-scale empirical evidence on the uptake of chemoradiation at population level. Worldwide, survival improvements have been extensive, but some countries still lag behind. Our findings may help clinicians involved in national and international tumor pathway boards to promote initiatives aimed at more extensive implementation of clinical guidelines.

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.

Pancreatic cancer survival by stage and age in seven high-income countries (ICBP SURVMARK-2): a population-based study.

BACKGROUND: The global burden of pancreatic cancer has steadily increased, while the prognosis after pancreatic cancer diagnosis remains poor. This study aims to compare the stage- and age-specific pancreatic cancer net survival (NS) for seven high-income countries: Australia, Canada, Denmark, Ireland, New Zealand, Norway, and United Kingdom. METHODS: The study included over 35,000 pancreatic cancer cases diagnosed during 2012-2014, followed through 31 December 2015. The stage- and age-specific NS were calculated using the Pohar-Perme estimator. RESULTS: Pancreatic cancer survival estimates were low across all 7 countries, with 1-year NS ranging from 21.1% in New Zealand to 30.9% in Australia, and 3-year NS from 6.6% in the UK to 10.9% in Australia. Most pancreatic cancers were diagnosed with distant stage, ranging from 53.9% in Ireland to 83.3% in New Zealand. While survival differences were evident between countries across all stage categories at one year after diagnosis, this survival advantage diminished, particularly in cases with distant stage. CONCLUSION: This study demonstrated the importance of stage and age at diagnosis in pancreatic cancer survival. Although progress has been made in improving pancreatic cancer prognosis, the disease is highly fatal and will remain so without major breakthroughs in the early diagnosis and management.

International differences in lung cancer survival by sex, histological type and stage at diagnosis: an ICBP SURVMARK-2 Study.

INTRODUCTION: Lung cancer has a poor prognosis that varies internationally when assessed by the two major histological subgroups (non-small cell (NSCLC) and small cell (SCLC)). METHOD: 236 114 NSCLC and 43 167 SCLC cases diagnosed during 2010-2014 in Australia, Canada, Denmark, Ireland, New Zealand, Norway and the UK were included in the analyses. One-year and 3-year age-standardised net survival (NS) was estimated by sex, histological type, stage and country. RESULTS: One-year and 3-year NS was consistently higher for Canada and Norway, and lower for the UK, New Zealand and Ireland, irrespective of stage at diagnosis. Three-year NS for NSCLC ranged from 19.7% for the UK to 27.1% for Canada for men and was consistently higher for women (25.3% in the UK; 35.0% in Canada) partly because men were diagnosed at more advanced stages. International differences in survival for NSCLC were largest for regional stage and smallest at the advanced stage. For SCLC, 3-year NS also showed a clear female advantage with the highest being for Canada (13.8% for women; 9.1% for men) and Norway (12.8% for women; 9.7% for men). CONCLUSION: Distribution of stage at diagnosis among lung cancer cases differed by sex, histological subtype and country, which may partly explain observed survival differences. Yet, survival differences were also observed within stages, suggesting that quality of treatment, healthcare system factors and prevalence of comorbid conditions may also influence survival. Other possible explanations include differences in data collection practice, as well as differences in histological verification, staging and coding across jurisdictions.

International variation in oesophageal and gastric cancer survival 2012-2014: differences by histological subtype and stage at diagnosis (an ICBP SURVMARK-2 population-based study).

OBJECTIVE: To provide the first international comparison of oesophageal and gastric cancer survival by stage at diagnosis and histological subtype across high-income countries with similar access to healthcare. METHODS: As part of the ICBP SURVMARK-2 project, data from 28 923 patients with oesophageal cancer and 25 946 patients with gastric cancer diagnosed during 2012-2014 from 14 cancer registries in seven countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway and the UK) were included. 1-year and 3-year age-standardised net survival were estimated by stage at diagnosis, histological subtype (oesophageal adenocarcinoma (OAC) and oesophageal squamous cell carcinoma (OSCC)) and country. RESULTS: Oesophageal cancer survival was highest in Ireland and lowest in Canada at 1 (50.3% vs 41.3%, respectively) and 3 years (27.0% vs 19.2%) postdiagnosis. Survival from gastric cancer was highest in Australia and lowest in the UK, for both 1-year (55.2% vs 44.8%, respectively) and 3-year survival (33.7% vs 22.3%). Most patients with oesophageal and gastric cancer had regional or distant disease, with proportions ranging between 56% and 90% across countries. Stage-specific analyses showed that variation between countries was greatest for localised disease, where survival ranged between 66.6% in Australia and 83.2% in the UK for oesophageal cancer and between 75.5% in Australia and 94.3% in New Zealand for gastric cancer at 1-year postdiagnosis. While survival for OAC was generally higher than that for OSCC, disparities across countries were similar for both histological subtypes. CONCLUSION: Survival from oesophageal and gastric cancer varies across high-income countries including within stage groups, particularly for localised disease. Disparities can partly be explained by earlier diagnosis resulting in more favourable stage distributions, and distributions of histological subtypes of oesophageal cancer across countries. Yet, differences in treatment, and also in cancer registration practice and the use of different staging methods and systems, across countries may have impacted the comparisons. While primary prevention remains key, advancements in early detection research are promising and will likely allow for additional risk stratification and survival improvements in the future.

Comparison of liver cancer incidence and survival by subtypes across seven high-income countries.

International comparison of liver cancer survival has been hampered due to varying standards and degrees for morphological verification and differences in coding practices. This article aims to compare liver cancer survival across the International Cancer Benchmarking Partnership's (ICBP) jurisdictions whilst trying to ensure that the estimates are comparable through a range of sensitivity analyses. Liver cancer incidence data from 21 jurisdictions in 7 countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway and the United Kingdom) were obtained from population-based registries for 1995-2014. Cases were categorised based on histological classification, age-groups, basis of diagnosis and calendar period. Age-standardised incidence rate (ASR) per 100 000 and net survival at 1 and 3 years after diagnosis were estimated. Liver cancer incidence rates increased over time across all ICBP jurisdictions, particularly for hepatocellular carcinoma (HCC) with the largest relative increase in the United Kingdom, increasing from 1.3 to 4.4 per 100 000 person-years between 1995 and 2014. Australia had the highest age-standardised 1-year and 3-year net survival for all liver cancers combined (48.7% and 28.1%, respectively) in the most recent calendar period, which was still true for morphologically verified tumours when making restrictions to ensure consistent coding and classification. Survival from liver cancers is poor in all countries. The incidence of HCC is increasing alongside the proportion of nonmicroscopically verified cases over time. Survival estimates for all liver tumours combined should be interpreted in this context. Care is needed to ensure that international comparisons are performed on appropriately comparable patients, with careful consideration of coding practice variations.

Risk factors for early-onset colorectal cancer: a population-based case-control study in Ontario, Canada.

PURPOSE: There has been an alarming increase in colorectal cancer (CRC) incidence among young adults aged < 50 years, and factors driving this upward trend are unknown. This study investigated associations between various medical, lifestyle, and dietary factors and risk of early-onset CRC (EO-CRC). METHODS: A population-based case-control study was conducted in Ontario, Canada during 2018-2019. EO-CRC cases aged 20-49 years (n = 175) were identified from the Ontario Cancer Registry; sex- and age group-matched controls (n = 253) were recruited through random digit dialing. Data on potential a priori risk factors were collected using a web-based self-reported questionnaire. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using multivariable logistic regression. RESULTS: Family history of CRC in a first- or second-degree relative (OR 2.37; 95% CI 1.47-3.84), longer sedentary time (≥ 10 vs. < 5 h/day, OR 1.93; 95% CI 1.02-3.65), greater consumption of sugary drinks (≥ 7 vs. < 1 drinks/week, OR 2.99; 95% CI 1.57-5.68), and a more Westernized dietary pattern (quartile 4 vs. 1, OR 1.92; 95% CI 1.01-3.66) were each associated with an increased risk of EO-CRC. Conversely, calcium supplement use (OR 0.53; 95% CI 0.31-0.92), history of allergy or asthma (OR 0.62; 95% CI 0.39-0.98), and greater parity in females (≥ 3 vs. nulliparity, OR 0.29; 95% CI 0.11-0.76) were each associated with a reduced risk. CONCLUSION: Modifiable factors, particularly sedentary behavior and unhealthy diet including sugary drink consumption, may be associated with EO-CRC risk. Our findings, if replicated, may help inform prevention strategies targeted at younger persons.

Estimating the future cancer management costs attributable to modifiable risk factors in Canada.

OBJECTIVES: An estimated 33-37% of incident cancers in Canada are attributable to modifiable risk factors. Interventions targeting these risk factors would minimize the substantial health and economic burdens Canadians face due to cancer. We estimate the future health and economic burden of cancer in Canada by incorporating data from the Canadian Population Attributable Risk of Cancer (ComPARe) study into OncoSim, a web-based microsimulation tool. METHODS: Using the integrated OncoSim population attributable risk and population impact measures, we evaluated risk factor-targeted intervention scenarios implemented in 2020, assuming the targeted risk factor prevalence reduction would be achieved by 2032 with a 12-year latency period. RESULTS: We estimate that smoking will be the largest contributor to cancer-related costs, with a cost of CAD $44.4 billion between 2032 and 2044. An estimated CAD $3.3 billion of the cost could be avoided with a 30% reduction in smoking prevalence by 2022. Following smoking, the next highest cancer management costs are associated with inadequate physical activity and excess body weight, accounting for CAD $10.7 billion ($2.7 billion avoidable) and CAD $9.8 billion ($3.2 billion avoidable), respectively. Avoidable costs for other risk factors range from CAD $90 million to CAD $2.5 billion. CONCLUSION: Interventions targeting modifiable cancer risk factors could prevent a substantial number of incident cancer cases and billions of dollars in cancer management costs. With limited budgets and rising costs in cancer care in Canada, these simulation models and results are valuable for researchers and policymakers to inform decisions and prioritize and evaluate intervention programs.

RéSUMé: OBJECTIFS: Il est estimé que de 33 % à 37 % des cancers incidents au Canada sont imputables à des facteurs de risque modifiables. Des interventions ciblant ces facteurs de risque réduiraient le fardeau sanitaire et économique considérable du cancer dans la population canadienne. Nous avons estimé le futur fardeau sanitaire et économique du cancer au Canada en intégrant les données de l'étude ComPARe (Canadian Population Attributable Risk of Cancer) dans l'outil de microsimulation en ligne OncoSim. MéTHODE: À l'aide des indicateurs d'impact dans la population et du risque attribuable dans la population intégrés dans OncoSim, nous avons évalué des scénarios d'intervention mis en œuvre en 2020 axés sur les facteurs de risque, en partant de l'hypothèse que la réduction de la prévalence des facteurs de risque ciblés serait atteinte d'ici 2032 avec une période de latence de 12 ans. RéSULTATS: Nous estimons que le tabagisme sera le facteur qui contribuera le plus aux coûts du cancer, avec un coût de 44,4 milliards $ CA entre 2032 et 2044. Il est estimé qu'une part de 3,3 milliards $ CA de ce coût pourrait être évitée en réduisant de 30 % la prévalence du tabagisme d'ici 2022. Après le tabagisme, les coûts de prise en charge du cancer les plus élevés sont associés à l'inactivité physique et au surpoids, qui représentent respectivement 10,7 milliard $ CA (dont 2,7 milliards $ évitables) et 9,8 milliards $ CA (dont 3,2 milliards $ évitables). Les coûts évitables pour d'autres facteurs de risque vont de 90 millions $ CA à 2,5 milliards $ CA. CONCLUSION: Des interventions ciblant les facteurs de risque de cancer modifiables pourraient prévenir un nombre considérable de cas de cancers incidents et épargner des milliards de dollars en coûts de prise en charge du cancer. Avec les budgets serrés et la hausse des coûts des soins du cancer au Canada, ces modèles de simulation et leurs résultats permettent aux chercheurs et aux responsables des politiques d'éclairer les décisions et de hiérarchiser et d'évaluer les programmes d'intervention.

Estimates of future cancer mortality attributable to modifiable risk factors in Canada.

OBJECTIVES: Modifiable lifestyle, environmental, and infectious risk factors associated with cancer impact both cancer incidence and mortality at the population level. Most studies estimating this burden focus on cancer incidence. However, because these risk factors are associated with cancers of disparate mortality rates, the burden associated with cancer incidence could differ from cancer mortality. Therefore, estimating the cancer mortality attributable to these risk factors provides additional insight into cancer prevention. Here, we estimated future cancer deaths and the number of avoidable deaths in Canada due to modifiable risk factors. METHODS: The projected cancer mortality data came from OncoSim, a web-based microsimulation tool. These data were applied to the methodological framework that we previously used to estimate the population attributable risks and the potential impact fractions of modifiable risk factors on Canadian cancer incidence. RESULTS: We estimated that most cancer deaths will be attributed to tobacco smoking with an average of 27,900 deaths annually from 2024 to 2047. If Canada's current trends in excess body weight continue, cancer deaths attributable to excess body weight would double from 2786 deaths in 2024 to 5604 deaths in 2047, becoming the second leading modifiable cause of cancer death. Applying targets to reduce these risk factors, up to 34,600 cancer deaths could be prevented from 2024 to 2047. CONCLUSION: Our simulated results complement our previous findings on the cancer incidence burden since decreasing the overall burden of cancer will be accelerated through a combination of decreasing cancer incidence and improving survival outcomes through improved treatments.

RéSUMé: OBJECTIFS: Les facteurs de risque modifiables associés au cancer (liés au mode de vie, à l'environnement, aux maladies infectieuses) ont des effets à la fois sur l'incidence du cancer et sur la mortalité par cancer à l'échelle de la population. La plupart des études qui estiment ce fardeau portent sur l'incidence du cancer. Cependant, comme les facteurs de risque susmentionnés sont associés à des cancers dont les taux de mortalité sont disparates, le fardeau associé à l'incidence du cancer pourrait différer de la mortalité par cancer. En conséquence, l'estimation de la mortalité par cancer imputable à ces facteurs de risque pourrait éclairer la prévention du cancer. Nous estimons ici les décès futurs par cancer et le nombre de décès évitables au Canada dus à des facteurs de risque modifiables. MéTHODE: Les données projetées sur la mortalité par cancer proviennent d'OncoSim, un outil de microsimulation en ligne. Elles ont été appliquées au cadre méthodologique que nous avions déjà utilisé pour estimer les risques attribuables dans la population et les fractions de l'incidence potentielle des facteurs de risque modifiables sur l'incidence canadienne du cancer. RéSULTATS: Selon nos estimations, entre 2024 et 2047, la plupart des décès par cancer seront imputés au tabagisme, qui causera en moyenne 27 900 décès par année. Si les tendances actuelles au Canada en matière de surpoids se maintiennent, les décès par cancer attribuables au surpoids doubleraient, passant de 2 786 décès en 2024 à 5 604 en 2047, et le surpoids deviendrait la deuxième cause modifiable de décès par cancer. En appliquant des cibles de réduction de ces facteurs de risque, jusqu'à 34 600 décès par cancer pourraient être évités entre 2024 et 2047. CONCLUSION: Les résultats de notre simulation confirment nos constatations antérieures sur le fardeau de l'incidence du cancer, car la diminution du fardeau global du cancer sera accélérée par une combinaison de la diminution de l'incidence du cancer et de l'amélioration des résultats de survie grâce à l'amélioration des traitements.

The impact of reclassifying cancers of unspecified histology on international differences in survival for small cell and non-small cell lung cancer (ICBP SurvMark-2 project).

Survival from lung cancer remains low, yet is the most common cancer diagnosed worldwide. With survival contrasting between the main histological groupings, small-cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), it is important to assess the extent that geographical differences could be from varying proportions of cancers with unspecified histology across countries. Lung cancer cases diagnosed 2010-2014, followed until 31 December 2015 were provided by cancer registries from seven countries for the ICBP SURVMARK-2 project. Multiple imputation was used to reassign cases with unspecified histology into SCLC, NSCLC and other. One-year and three-year age-standardised net survival were estimated by histology, sex, age group and country. In all, 404 617 lung cancer cases were included, of which 47 533 (11.7%) and 262 040 (64.8%) were SCLC and NSCLC. The proportion of unspecified cases varied, from 11.2% (Denmark) to 29.0% (The United Kingdom). After imputation with unspecified histology, survival variations remained: 1-year SCLC survival ranged from 28.0% (New Zealand) to 35.6% (Australia) NSCLC survival from 39.4% (The United Kingdom) to 49.5% (Australia). The largest survival change after imputation was for 1-year NSCLC (4.9 percentage point decrease). Similar variations were observed for 3-year survival. The oldest age group had lowest survival and largest decline after imputation. International variations in SCLC and NSCLC survival are only partially attributable to differences in the distribution of unspecified histology. While it is important that registries and clinicians aim to improve completeness in classifying cancers, it is likely that other factors play a larger role, including underlying risk factors, stage, comorbidity and care management which warrants investigation.

The histology of brain tumors for 67 331 children and 671 085 adults diagnosed in 60 countries during 2000-2014: a global, population-based study (CONCORD-3).

BACKGROUND: Global variations in survival for brain tumors are very wide when all histological types are considered together. Appraisal of international differences should be informed by the distribution of histology, but little is known beyond Europe and North America. METHODS: The source for the analysis was the CONCORD database, a program of global surveillance of cancer survival trends, which includes the tumor records of individual patients from more than 300 population-based cancer registries. We considered all patients aged 0-99 years who were diagnosed with a primary brain tumor during 2000-2014, whether malignant or nonmalignant. We presented the histology distribution of these tumors, for patients diagnosed during 2000-2004, 2005-2009, and 2010-2014. RESULTS: Records were submitted from 60 countries on 5 continents, 67 331 for children and 671 085 for adults. After exclusion of irrelevant morphology codes, the final study population comprised 60 783 children and 602 112 adults. Only 59 of 60 countries covered in CONCORD-3 were included because none of the Mexican records were eligible. We defined 12 histology groups for children, and 11 for adults. In children (0-14 years), the proportion of low-grade astrocytomas ranged between 6% and 50%. Medulloblastoma was the most common subtype in countries where low-grade astrocytoma was less commonly reported. In adults (15-99 years), the proportion of glioblastomas varied between 9% and 69%. International comparisons were made difficult by wide differences in the proportion of tumors with unspecified histology, which accounted for up to 52% of diagnoses in children and up to 65% in adults. CONCLUSIONS: To our knowledge, this is the first account of the global histology distribution of brain tumors, in children and adults. Our findings provide insights into the practices and the quality of cancer registration worldwide.

The impact of excluding or including Death Certificate Initiated (DCI) cases on estimated cancer survival: A simulation study.

BACKGROUND: Population-based cancer registries strive to cover all cancer cases diagnosed within the population, but some cases will always be missed and no register is 100 % complete. Many cancer registries use death certificates to identify additional cases not captured through other routine sources, to hopefully add a large proportion of the missed cases. Cases notified through this route, who would not have been captured without death certificate information, are referred to as Death Certificate Initiated (DCI) cases. Inclusion of DCI cases in cancer registries increases completeness and is important for estimating cancer incidence. However, inclusion of DCI cases will generally lead to biased estimates of cancer survival, but the same is often also true if excluding DCI cases. Missed cases are probably not a random sample of all cancer cases, but rather cases with poor prognosis. Further, DCI cases have poorer prognosis than missed cases in general, since they have all died with cancer mentioned on the death certificates. METHODS: We performed a simulation study to estimate the impact of including or excluding DCI cases on cancer survival estimates, under different scenarios. RESULTS: We demonstrated that including DCI cases underestimates survival. The exclusion of DCI cases gives unbiased survival estimates if missed cases are a random sample of all cancer cases, while survival is overestimated if these have poorer prognosis. CONCLUSION: In our most extreme scenarios, with 25 % of cases initially missed, the usual practice of including DCI cases underestimated 5-year survival by at most 3 percentage points.

International trends in oesophageal cancer survival by histological subtype between 1995 and 2014.

INTRODUCTION: Survival from oesophageal cancer remains poor, even across high-income countries. Ongoing changes in the epidemiology of the disease highlight the need for survival assessments by its two main histological subtypes, adenocarcinoma (AC) and squamous cell carcinoma (SCC). METHODS: The ICBP SURVMARK-2 project, a platform for international comparisons of cancer survival, collected cases of oesophageal cancer diagnosed 1995 to 2014, followed until 31st December 2015, from cancer registries covering seven participating countries with similar access to healthcare (Australia, Canada, Denmark, Ireland, New Zealand, Norway and the UK). 1-year and 3-year age-standardised net survival alongside incidence rates were calculated by country, subtype, sex, age group and period of diagnosis. RESULTS: 111 894 cases of AC and 73 408 cases of SCC were included in the analysis. Marked improvements in survival were observed over the 20-year period in each country, particularly for AC, younger age groups and 1 year after diagnosis. Survival was consistently higher for both subtypes in Australia and Ireland followed by Norway, Denmark, New Zealand, the UK and Canada. During 2010 to 2014, survival was higher for AC compared with SCC, with 1-year survival ranging from 46.9% (Canada) to 54.4% (Ireland) for AC and 39.6% (Denmark) to 53.1% (Australia) for SCC. CONCLUSION: Marked improvements in both oesophageal AC and SCC survival suggest advances in treatment. Less marked improvements 3 years after diagnosis, among older age groups and patients with SCC, highlight the need for further advances in early detection and treatment of oesophageal cancer alongside primary prevention to reduce the overall burden from the disease.

Colon and rectal cancer survival in seven high-income countries 2010-2014: variation by age and stage at diagnosis (the ICBP SURVMARK-2 project).

OBJECTIVES: As part of the International Cancer Benchmarking Partnership (ICBP) SURVMARK-2 project, we provide the most recent estimates of colon and rectal cancer survival in seven high-income countries by age and stage at diagnosis. METHODS: Data from 386 870 patients diagnosed during 2010-2014 from 19 cancer registries in seven countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway and the UK) were analysed. 1-year and 5-year net survival from colon and rectal cancer were estimated by stage at diagnosis, age and country, RESULTS: (One1-year) and 5-year net survival varied between (77.1% and 87.5%) 59.1% and 70.9% and (84.8% and 90.0%) 61.6% and 70.9% for colon and rectal cancer, respectively. Survival was consistently higher in Australia, Canada and Norway, with smaller proportions of patients with metastatic disease in Canada and Australia. International differences in (1-year) and 5-year survival were most pronounced for regional and distant colon cancer ranging between (86.0% and 94.1%) 62.5% and 77.5% and (40.7% and 56.4%) 8.0% and 17.3%, respectively. Similar patterns were observed for rectal cancer. Stage distribution of colon and rectal cancers by age varied across countries with marked survival differences for patients with metastatic disease and diagnosed at older ages (irrespective of stage). CONCLUSIONS: Survival disparities for colon and rectal cancer across high-income countries are likely explained by earlier diagnosis in some countries and differences in treatment for regional and distant disease, as well as older age at diagnosis. Differences in cancer registration practice and different staging systems across countries may have impacted the comparisons.

A comparative analysis: international variation in PET-CT service provision in oncology-an International Cancer Benchmarking Partnership study.

OBJECTIVE: To explore differences in position emission tomography-computed tomography (PET-CT) service provision internationally to further understand the impact variation may have upon cancer services. To identify areas of further exploration for researchers and policymakers to optimize PET-CT services and improve the quality of cancer services. DESIGN: Comparative analysis using data based on pre-defined PET-CT service metrics from PET-CT stakeholders across seven countries. This was further informed via document analysis of clinical indication guidance and expert consensus through round-table discussions of relevant PET-CT stakeholders. Descriptive comparative analyses were produced on use, capacity and indication guidance for PET-CT services between jurisdictions. SETTING: PET-CT services across 21 jurisdictions in seven countries (Australia, Denmark, Canada, Ireland, New Zealand, Norway and the UK). PARTICIPANTS: None. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): None. RESULTS: PET-CT service provision has grown over the period 2006-2017, but scale of increase in capacity and demand is variable. Clinical indication guidance varied across countries, particularly for small-cell lung cancer staging and the specific acknowledgement of gastric cancer within oesophagogastric cancers. There is limited and inconsistent data capture, coding, accessibility and availability of PET-CT activity across countries studied. CONCLUSIONS: Variation in PET-CT scanner quantity, acquisition over time and guidance upon use exists internationally. There is a lack of routinely captured and accessible PET-CT data across the International Cancer Benchmarking Partnership countries due to inconsistent data definitions, data linkage issues, uncertain coverage of data and lack of specific coding. This is a barrier in improving the quality of PET-CT services globally. There needs to be greater, richer data capture of diagnostic and staging tools to facilitate learning of best practice and optimize cancer services.

Exploring the impact of cancer registry completeness on international cancer survival differences: a simulation study.

BACKGROUND: Data from population-based cancer registries are often used to compare cancer survival between countries or regions. The ICBP SURVMARK-2 study is an international partnership aiming to quantify and explore the reasons behind survival differences across high-income countries. However, the magnitude and relevance of differences in cancer survival between countries have been questioned, as it is argued that observed survival variations may be explained, at least in part, by differences in cancer registration practice, completeness and the availability and quality of the respective data sources. METHODS: As part of the ICBP SURVMARK-2 study, we used a simulation approach to better understand how differences in completeness, the characteristics of those missed and inclusion of cases found from death certificates can impact on cancer survival estimates. RESULTS: Bias in 1- and 5-year net survival estimates for 216 simulated scenarios is presented. Out of the investigated factors, the proportion of cases not registered through sources other than death certificates, had the largest impact on survival estimates. CONCLUSION: Our results show that the differences in registration practice between participating countries could in our most extreme scenarios explain only a part of the largest observed differences in cancer survival.

Age disparities in stage-specific colon cancer survival across seven countries: An International Cancer Benchmarking Partnership SURVMARK-2 population-based study.

We sought to understand the role of stage at diagnosis in observed age disparities in colon cancer survival among people aged 50 to 99 years using population-based cancer registry data from seven high-income countries: Australia, Canada, Denmark, Ireland, New Zealand, Norway and the United Kingdom. We used colon cancer incidence data for the period 2010 to 2014. We estimated the 3-year net survival, as well as the 3-year net survival conditional on surviving at least 6 months and 1 year after diagnosis, by country and stage at diagnosis (categorised as localised, regional or distant) using flexible parametric excess hazard regression models. In all countries, increasing age was associated with lower net survival. For example, 3-year net survival (95% confidence interval) was 81% (80-82) for 50 to 64 year olds and 58% (56-60) for 85 to 99 year olds in Australia, and 74% (73-74) and 39% (39-40) in the United Kingdom, respectively. Those with distant stage colon cancer had the largest difference in colon cancer survival between the youngest and the oldest patients. Excess mortality for the oldest patients with localised or regional cancers was observed during the first 6 months after diagnosis. Older patients diagnosed with localised (and in some countries regional) stage colon cancer who survived 6 months after diagnosis experienced the same survival as their younger counterparts. Further studies examining other prognostic clinical factors such as comorbidities and treatment, and socioeconomic factors are warranted to gain further understanding of the age disparities in colon cancer survival.

A Bayesian shared components modeling approach to develop small area indicators of social determinants of health with measures of uncertainty.

OBJECTIVES: Existing Canadian social determinants of health (SDOH) indicators do not quantify uncertainty to identify priority areas. The objectives of this methodologic study were: (1) to estimate and map small area (dissemination area) shared and variable-specific SDOH indicators with measures of uncertainty using a Bayesian model that accounts for spatial dependence; (2) to quantify geographic variation in the SDOH indicators and their contribution to a shared indicator; and (3) to assess the SDOH indicators' associations with behavioural risk factors and their consistency with the Ontario Marginalization Index (ON-Marg). METHODS: Lower education-, income-, unemployment-, living alone- and visible minority-related variables used in existing Canadian SDOH indices were fit as dependent variables to a Bayesian model to produce area-based SDOH indicators that were mapped with measures of uncertainty in two study areas. The fractions of spatial variation explained by the model components were computed. Bayesian analysis of variance was used to examine the SDOH indicator associations with behavioural risk factors and their consistency with ON-Marg examined using Pearson's correlation coefficient. RESULTS: The shared component was strongly associated with material deprivation (i.e., income) in each study area; however, variable-specific SDOH indicators were important too. The SDOH indicators were associated with behavioural risk factors for chronic disease, particularly alcohol consumption and smoking, and the shared component estimates were consistent with the ON-Marg material deprivation. CONCLUSIONS: The Bayesian approach to produce SDOH indicators met the three study objectives and as such provides a new approach to prioritize areas that may experience health inequalities.

Exploring variations in ovarian cancer survival by age and stage (ICBP SurvMark-2): A population-based study.

OBJECTIVE: The study aims to evaluate the differences in ovarian cancer survival by age and stage at diagnosis within and across seven high-income countries. METHODS: We analyzed data from 58,161 women diagnosed with ovarian cancer during 2010-2014, followed until 31 December 2015, from 21 population-based cancer registries in Australia, Canada, Denmark, Ireland, New Zealand, Norway, and United Kingdom. Comparisons of 1-year and 3-year age- and stage-specific net survival (NS) between countries were performed using the period analysis approach. RESULTS: Minor variation in the stage distribution was observed between countries, with most women being diagnosed with 'distant' stage (ranging between 64% in Canada and 71% in Norway). The 3-year all-ages NS ranged from 45 to 57% with Australia (56%) and Norway (57%) demonstrating the highest survival. The proportion of women with 'distant' stage was highest for those aged 65-74 and 75-99 years and varied markedly between countries (range:72-80% and 77-87%, respectively). The oldest age group had the lowest 3-year age-specific survival (20-34%), and women aged 65-74 exhibited the widest variation across countries (3-year NS range: 40-60%). Differences in survival between countries were particularly stark for the oldest age group with 'distant' stage (3-year NS range: 12% in Ireland to 24% in Norway). CONCLUSIONS: International variations in ovarian cancer survival by stage exist with the largest differences observed in the oldest age group with advanced disease. This finding endorses further research investigating international differences in access to and quality of treatment, and prevalence of comorbid conditions particularly in older women with advanced disease.