Global burden of colorectal cancer in 2020 and 2040: incidence and mortality estimates from GLOBOCAN.

OBJECTIVE: Colorectal cancer (CRC) is the third most common cancer worldwide. The geographical and temporal burden of this cancer provides insights into risk factor prevalence and progress in cancer control strategies. We examine the current and future burden of CRC in 185 countries in 2020 and 2040. METHODS: Data on CRC cases and deaths were extracted from the GLOBOCAN database for the year 2020. Age-standardised incidence and mortality rates were calculated by sex, country, world region and Human Development Index (HDI) for 185 countries. Age-specific rates were also estimated. The predicted number of cases and deaths in 2040 were calculated based on global demographic projections by HDI. RESULTS: Over 1.9 million new CRC cases and 930 000 deaths were estimated in 2020. Incidence rates were highest in Australia/ New Zealand and European regions (40.6 per 100 000, males) and lowest in several African regions and Southern Asia (4.4 per 100 000, females). Similar patterns were observed for mortality rates, with the highest observed in Eastern Europe (20.2 per 100 000, males) and the lowest in Southern Asia (2.5 per 100 000, females). The burden of CRC is projected to increase to 3.2 million new cases and 1.6 million deaths by 2040 with most cases predicted to occur in high or very high HDI countries. CONCLUSIONS: CRC is a highly frequent cancer worldwide, and largely preventable through changes in modifiable risk factors, alongside the detection and removal of precancerous lesions. With increasing rates in transitioning countries and younger adults, there is a pressing need to better understand and act on findings to avert future cases and deaths from the disease.

Population-based investigation of common and deviating patterns of gastric cancer and oesophageal cancer incidence across populations and time.

BACKGROUND: The subtypes of gastric cancer (GC) and oesophageal cancer (EC) manifest distinct epidemiological profiles. Here, we aim to examine correlations in their incidence rates and to compare their temporal changes globally, both overall and by subtype. METHODS: Long-term incidence data were obtained from population-based registries available from the Cancer Incidence in Five Continents series. Variation in the occurrence of EC and GC (overall and by subtype) was assessed using the GC:EC ratio of sex-specific age-standardised rates (ASR) in 2008-2012. Average annual per cent changes were estimated to assess temporal trends during 1998-2012. RESULTS: ASRs for GC and EC varied remarkably across and within world regions. In the countries evaluated, the GC:EC ratio in men exceeded 10 in several South American countries, Algeria and Republic of Korea, while EC dominated in most sub-Saharan African countries. High rates of both cardia gastric cancer and oesophageal squamous cell carcinoma (ESCC) were observed in several Asian populations. Non-cardia gastric cancer rates correlated positively with ESCC rates (r=0.60) and negatively with EAC (r=-0.79). For the time trends, while GC incidence has been uniformly decreasing by on average 2%-3% annually over 1998-2012 in most countries, trends for EC depend strongly on histology, with several but not all countries experiencing increases in EAC and decreases in ESCC. CONCLUSIONS: Correlations between GC and EC incidence rates across populations are positive or inverse depending on the GC subsite and EC subtype. Multisite studies that include a combination of populations whose incidence rates follow and deviate from these patterns may be aetiologically informative.

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.

The Global Landscape of Esophageal Squamous Cell Carcinoma and Esophageal Adenocarcinoma Incidence and Mortality in 2020 and Projections to 2040: New Estimates From GLOBOCAN 2020.

BACKGROUND & AIMS: The aim of this study was to provide an overview of the burden of esophageal cancer in 185 countries in 2020 and projections for the year 2040. METHODS: Estimates of esophageal cancer cases and deaths were extracted from the GLOBOCAN database for 2020. Age-standardized incidence and mortality rates were calculated overall, by sex, histologic subtype (adenocarcinoma [AC] and squamous cell carcinoma [SCC]), country, and level of human development for 185 countries. The predicted burden of incidence and mortality in 2040 was calculated based on global demographic projections. RESULTS: Globally, there were an estimated 604,100 new cases of, and 544,100 deaths from, esophageal cancer in 2020, corresponding to age-standardized incidence and mortality rates of 6.3 and 5.6 per 100,000, respectively. Most cases were SCCs (85% [512,500 cases]) and 14% (85,700 cases) were ACs. Incidence and mortality rates were 2- to 3-fold higher in male (9.3 and 8.2, respectively) compared with female (3.6 and 3.2, respectively) individuals. Global variations in incidence and mortality were observed across countries and world regions; the highest rates occurred in Eastern Asia and Southern and Eastern Africa and the lowest occurred in Western Africa and Central America regions. If rates remain stable, 957,000 new cases (141,300 AC cases and 806,000 SCC cases) and 880,000 deaths from esophageal cancer are expected in 2040. CONCLUSIONS: These updated estimates of the global burden of esophageal cancer represent an important baseline for setting priorities in policy making and developing and accelerating cancer control initiatives to reduce the current and projected burden. Although primary prevention remains key, screening and early detection represent important components of esophageal cancer control in high-risk populations.

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.

Global and national trends in the age-specific sex ratio of esophageal cancer and gastric cancer by subtype.

A male predominance was observed in esophageal and gastric cancers, though present limited data has revealed variations by age. We aim to investigate the global age-specific sex differences in esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAC), gastric cardia cancer (GCC) and gastric noncardia cancer (GNCC). Data on esophageal and gastric cancers incidence by diagnosis year, sex, histology, subsite and age group were extracted from 171 registries in 54 countries included in the last two volumes (X and XI, 2003-2012) of Cancer Incidence in Five Continents, which contributing to over 80% of the global burdens of these cancers. Age-standardized incidence rates (ASIRs) and male-to-female ASIRs ratios were estimated for esophageal and gastric cancers, by histological subtype and subsite, globally and by country. We consistently observed a male predominance in esophageal and gastric cancers across the world from 2003 to 2012, with male-to-female ASIRs ratios of 6.7:1 for EAC, 3.3:1 for ESCC, 4.0:1 for GCC and 2.1:1 for GNCC. The sex differences were consistent across time periods but varied significantly by age across the life span. Across the four cancer types, the male-to-female incidence rate ratios increased from young ages, approaching a peak at ages 60-64, but sharply declined thereafter. Similar "low-high-low" trends of age-specific sex ratio were observed in other digestive cancers including liver, pancreas, colon and rectum with peak ages ranging from 50 to 65. Age-dependent risk factors warrant further investigation to aid our understanding of the underlying etiologies of esophageal and gastric cancers by histological subtype and subsite.

Five ways to improve international comparisons of cancer survival: lessons learned from ICBP SURVMARK-2.

BACKGROUND: Comparisons of population-based cancer survival between countries are important to benchmark the overall effectiveness of cancer management. The International Cancer Benchmarking Partnership (ICBP) Survmark-2 study aims to compare survival in seven high-income countries across eight cancer sites and explore reasons for the observed differences. A critical aspect in ensuring comparability in the reported survival estimates are similarities in practice across cancer registries. While ICBP Survmark-2 has shown these differences are unlikely to explain the observed differences in cancer-specific survival between countries, it is important to keep in mind potential biases linked to registry practice and understand their likely impact. METHODS: Based on experiences gained within ICBP Survmark-2, we have developed a set of recommendations that seek to optimally harmonise cancer registry datasets to improve future benchmarking exercises. RESULTS: Our recommendations stem from considering the impact on cancer survival estimates in five key areas: (1) the completeness of the registry and the availability of registration sources; (2) the inclusion of death certification as a source of identifying cases; (3) the specification of the date of incidence; (4) the approach to handling multiple primary tumours and (5) the quality of linkage of cases to the deaths register. CONCLUSION: These recommendations seek to improve comparability whilst maintaining the opportunity to understand and act upon international variations in outcomes among cancer patients.

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.

Global burden of primary liver cancer in 2020 and predictions to 2040.

BACKGROUND & AIMS: The burden of liver cancer varies across the world. Herein, we present updated estimates of the current global burden of liver cancer (incidence and mortality) and provide predictions of the number of cases/deaths to 2040. METHODS: We extracted data on primary liver cancer cases and deaths from the GLOBOCAN 2020 database, which includes 185 countries. Age-standardised incidence and mortality rates (ASRs) per 100,000 person-years were calculated. Cases and deaths up to the year 2040 were predicted based on incidence and mortality rates for 2020 and global demographic projections to 2040. RESULTS: In 2020, an estimated 905,700 people were diagnosed with, and 830,200 people died from, liver cancer globally. Global ASRs for liver cancer were 9.5 and 8.7 for new cases and deaths, respectively, per 100,000 people and were highest in Eastern Asia (17.8 new cases, 16.1 deaths), Northern Africa (15.2 new cases, 14.5 deaths), and South-Eastern Asia (13.7 new cases, 13.2 deaths). Liver cancer was among the top three causes of cancer death in 46 countries and was among the top five causes of cancer death in 90 countries. ASRs of both incidence and mortality were higher among males than females in all world regions (male:female ASR ratio ranged between 1.2-3.6). The number of new cases of liver cancer per year is predicted to increase by 55.0% between 2020 and 2040, with a possible 1.4 million people diagnosed in 2040. A predicted 1.3 million people could die from liver cancer in 2040 (56.4% more than in 2020). CONCLUSIONS: Liver cancer is a major cause of death in many countries, and the number of people diagnosed with liver cancer is predicted to rise. Efforts to reduce the incidence of preventable liver cancer should be prioritised. LAY SUMMARY: The burden of liver cancer varies across the world. Liver cancer was among the top three causes of cancer death in 46 countries and was among the top five causes of cancer death in 90 countries worldwide. We predict the number of cases and deaths will rise over the next 20 years as the world population grows. Primary liver cancer due to some causes is preventable if control efforts are prioritised and the predicted rise in cases may increase the need for resources to manage care of patients with liver cancer.

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.

Impact of cumulative body mass index and cardiometabolic diseases on survival among patients with colorectal and breast cancer: a multi-centre cohort study.

BACKGROUND: Body mass index (BMI) and cardiometabolic comorbidities such as cardiovascular disease and type 2 diabetes have been studied as negative prognostic factors in cancer survival, but possible dependencies in the mechanisms underlying these associations remain largely unexplored. We analysed these associations in colorectal and breast cancer patients. METHODS: Based on repeated BMI assessments of cancer-free participants from four European countries in the European Prospective Investigation into Cancer and nutrition (EPIC) study, individual BMI-trajectories reflecting predicted mean BMI between ages 20 to 50 years were estimated using a growth curve model. Participants with incident colorectal or breast cancer after the age of 50 years were included in the survival analysis to study the prognostic effect of mean BMI and cardiometabolic diseases (CMD) prior to cancer. CMD were defined as one or more chronic conditions among stroke, myocardial infarction, and type 2 diabetes. Hazard ratios (HRs) and confidence intervals (CIs) of mean BMI and CMD were derived using multivariable-adjusted Cox proportional hazard regression for mean BMI and CMD separately and both exposures combined, in subgroups of localised and advanced disease. RESULTS: In the total cohort of 159,045 participants, there were 1,045 and 1,620 eligible patients of colorectal and breast cancer. In colorectal cancer patients, a higher BMI (by 1 kg/m2) was associated with a 6% increase in risk of death (95% CI of HR: 1.02-1.10). The HR for CMD was 1.25 (95% CI: 0.97-1.61). The associations for both exposures were stronger in patients with localised colorectal cancer. In breast cancer patients, a higher BMI was associated with a 4% increase in risk of death (95% CI: 1.00-1.08). CMDs were associated with a 46% increase in risk of death (95% CI: 1.01-2.09). The estimates and CIs for BMI remained similar after adjustment for CMD and vice versa. CONCLUSIONS: Our results suggest that cumulative exposure to higher BMI during early to mid-adulthood was associated with poorer survival in patients with breast and colorectal cancer, independent of CMD prior to cancer diagnosis. The association between a CMD diagnosis prior to cancer and survival in patients with breast and colorectal cancer was independent of BMI.

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.

Population-based cancer staging for oesophageal, gastric, and pancreatic cancer 2012-2014: International Cancer Benchmarking Partnership SurvMark-2.

Cancer stage at diagnosis is important information for management and treatment of individual patients as well as in epidemiological studies to evaluate effectiveness of health care system in managing cancer patients. Population-based studies to examine international disparities on cancer survival by stage, however, has been challenging due to the lack of international standardization on recording stage information and variation in stage completeness across regions and countries. The International Cancer Benchmarking Partnership (ICBP) previously assessed the availability and comparability of staging information for colorectal, lung, female breast and ovarian cancers. Stage conversion algorithms were developed to aggregate and map all stage information into a single staging system to allow international comparison by stage at diagnosis. In this article, we developed stage conversion algorithms for three additional cancers, namely oesophageal, gastric and pancreatic cancers. We examined all stage information available, evaluated stage completeness, applied each stage conversion algorithm, and assessed the magnitude of misclassification using data from six Canadian cancer registries (Alberta, Manitoba, Newfoundland, Nova Scotia, Prince Edward Island and Saskatchewan). In addition, we discussed five recommendations for registries to improve international cancer survival comparison by stage: (a) improve collection and completeness of staging data; (b) promote a comparable definition for stage at diagnosis; (c) promote the use of a common stage classification system; (d) record versions of staging classifications and (e) use multiple data sources for valid staging data.

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.

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.

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.

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.

Global Burden of 5 Major Types of Gastrointestinal Cancer.

BACKGROUND & AIMS: There were an estimated 4.8 million new cases of gastrointestinal (GI) cancers and 3.4 million related deaths, worldwide, in 2018. GI cancers account for 26% of the global cancer incidence and 35% of all cancer-related deaths. We investigated the global burden from the 5 major GI cancers, as well as geographic and temporal trends in cancer-specific incidence and mortality. METHODS: Data on primary cancers of the esophagus, stomach, colorectum, liver, and pancreas were extracted from the GLOBOCAN database for the year 2018, as well as from the Cancer Incidence in 5 Continents series, and the World Health Organization mortality database from 1960 onward. Age-standardized incidence and mortality rates were calculated by sex, country, and level of human development. RESULTS: We observed geographic and temporal variations in incidence and mortality for all 5 types of GI cancers. Esophageal, gastric, and liver cancers were more common in Asia than in other parts of the world, and the burden from colorectal and pancreatic cancers was highest in Europe and North America. There was a uniform decrease in gastric cancer incidence, but an increasing incidence of colorectal cancer in formerly low-incidence regions during the studied time period. We found slight increases in incidence of liver and pancreatic cancer in some high-income regions. CONCLUSIONS: Although the incidence of some GI cancer types has decreased, this group of malignancies continues to pose major challenges to public health. Primary and secondary prevention measures are important for controlling these malignancies-most importantly reducing consumption of tobacco and alcohol, obesity control, immunizing populations against hepatitis B virus infection, and screening for colorectal cancer.

International Trends in Esophageal Squamous Cell Carcinoma and Adenocarcinoma Incidence.

INTRODUCTION: We aimed to improve our understanding of the epidemiology of squamous cell carcinoma and adenocarcinoma of the esophagus. METHODS: We estimated average annual percent change and analyzed age-period-cohort trends on population-based cancer data. RESULTS: We found decreases in squamous cell carcinoma incidence in half of male populations (largest decrease in US black males [average annual percent change -7.6]) and increases in adenocarcinoma incidence in nearly a third of populations. Trends may be associated with a mix of birth cohort and period effects. DISCUSSION: More complete data and evidence are needed to conclude the reasons for the observed trends (see Visual Abstract, Supplementary Digital Content 4, http://links.lww.com/AJG/B823).