TNM stage in the Nordic Cancer Registries 2004-2016: Registration and availability.

BACKGROUND AND PURPOSE: Stage at cancer diagnosis is an important predictor of cancer survival. TNM stage is constructed for anatomic solid cancer diagnoses from tumor size (T), nodal spread (N) and distant metastasis (M) and categorized in groups 0-I, II, II and IV. TNM stage is imperative in cancer diagnosis, management and control, and of high value in cancer surveillance, for example, monitoring of stage distributions. This study yields an overview of TNM availability and trends in stage distribution in the Nordic countries for future use in monitoring and epidemiologic studies. MATERIAL AND METHODS: TNM information was acquired from the cancer registries in Denmark, Norway, Sweden, and Iceland during 2004-2016 for 26 cancer sites in the three former countries and four in Iceland. We studied availability, comparability, and distribution of TNM stage in three periods: 2004-2008, 2009-2013, and 2014-2016, applying a previously validated algorithm of 'N0M0 for NXMX'. For cancers of colon, rectum, lung, breast, and kidney, we examined TNM stage-specific 1-year relative survival to evaluate the quality in registration of TNM between countries. RESULTS: Denmark, Sweden, and Iceland exhibited available TNM stage proportions of 75-95% while proportions were lower in Norway. Proportions increased in Sweden over time but decreased in Denmark. One-year relative survival differed substantially more between TNM stages than between countries emphasizing that TNM stage is an important predictor for survival and that stage recording is performed similarly in the Nordic countries. INTERPRETATION: Assessment and registration of TNM stage is an imperative tool in evaluations of trends in cancer survival between the Nordic countries.

Have the recent advancements in cancer therapy and survival benefitted patients of all age groups across the Nordic countries? NORDCAN survival analyses 2002-2021.

BACKGROUND: Since the early 2000s, overall and site-specific cancer survival have improved substantially in the Nordic countries. We evaluated whether the improvements have been similar across countries, major cancer types, and age groups. MATERIAL AND METHODS: Using population-based data from the five Nordic cancer registries recorded in the NORDCAN database, we included a cohort of 1,525,854 men and 1,378,470 women diagnosed with cancer (except non-melanoma skin cancer) during 2002-2021, and followed for death until 2021. We estimated 5-year relative survival (RS) in 5-year calendar periods, and percentage points (pp) differences in 5-year RS from 2002-2006 until 2017-2021. Separate analyses were performed for eight cancer sites (i.e. colorectum, pancreas, lung, breast, cervix uteri, kidney, prostate, and melanoma of skin). RESULTS: Five-year RS improved across nearly all cancer sites in all countries (except Iceland), with absolute differences across age groups ranging from 1 to 21 pp (all cancer sites), 2 to 20 pp (colorectum), -1 to 36 pp (pancreas), 2 to 28 pp (lung), 0 to 9 pp (breast), -11 to 26 pp (cervix uteri), 2 to 44 pp (kidney), -2 to 23 pp (prostate) and -3 to 30 pp (skin melanoma). The oldest patients (80-89 years) exhibited lower survival across all countries and sites, although with varying improvements over time. INTERPRETATION: Nordic cancer patients have generally experienced substantial improvements in cancer survival during the last two decades, including major cancer sites and age groups. Although survival has improved over time, older patients remain at a lower cancer survival compared to younger patients.

Influence of various assumptions for the individual TNM components on the TNM stage using Nordic cancer registry data.

BACKGROUND: The stage at diagnosis is one of the most important predictors for cancer survival. TNM stage is constructed from T (tumor size), N (nodal spread), and M (distant metastasis) components. In many notifications to cancer registries, TNM information is incomplete with unknown N and/or M. We aimed to evaluate the influence of various assumptions for recoding missing N (NX) and M (MX) as N0 and M0 on the proportion with available TNM stage, stage-distribution, and stage-specific relative survival. MATERIAL AND METHODS: We identified 140,201 patients diagnosed with incident cancer of the colon, rectum, lung, breast, or kidney during 2014-2016 in Denmark, Norway, Sweden, or Iceland. Information on TNM were obtained from cancer registry records used for an update of the Nordic cancer statistics database NORDCAN. Patients were followed for death or emigration through 2017. We calculated proportions of available TNM stage, stage distribution, and stage-specific relative survival under different approaches for each cancer site and country. RESULTS: Application of the assumptions yielded higher numbers of cases with available TNM stage for stages 0-I, II, and III. We observed only minor differences in stage-specific one-year relative survival when applying N0M0 for missing N and M, especially for high completeness of TNM registrations, whereas relative survival for remaining cases with missing TNM stage declined substantially. CONCLUSION: We found no major changes in stage-specific one-year relative survival applying N0M0 for NXMX. We conclude that complete TNM information is preferable to making assumptions, but it seems reasonable to consider assuming N0M0 for missing N and M in future studies based on the Nordic cancer registries. An automatic algorithm, though, is not recommended without considering potential area-specific reasons for frequent use of NX and MX. Clinicians should be urged to report complete TNM information to improve surveillance of the TNM stage.

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.

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.

Age-specific survival trends and life-years lost in women with breast cancer 1990-2016: the NORDCAN survival studies.

BACKGROUND: A recent overview of cancer survival trends 1990-2016 in the Nordic countries reported continued improvements in age-standardized breast cancer survival among women. The aim was to estimate age-specific survival trends over calendar time, including life-years lost, to evaluate if improvements have benefited patients across all ages in the Nordic countries. METHODS: Data on breast cancers diagnosed 1990-2016 in Denmark, Finland, Iceland, Norway, and Sweden were obtained from the NORDCAN database. Age-standardized and age-specific relative survival (RS) was estimated using flexible parametric models, as was reference-adjusted crude probabilities of death and life-years lost. RESULTS: Age-standardized period estimates of 5-year RS in women diagnosed with breast cancer ranged from 87% to 90% and 10-year RS from 74% to 85%. Ten-year RS increased with 15-18 percentage points from 1990 to 2016, except in Sweden (+9 percentage points) which had the highest survival in 1990. The largest improvements were observed in Denmark, where a previous survival disadvantage diminished. Most recent 5-year crude probabilities of cancer death ranged from 9% (Finland, Sweden) to 12% (Denmark, Iceland), and life-years lost from 3.3 years (Finland) to 4.6 years (Denmark). Although survival improvements were consistent across different ages, women aged ≥70 years had the lowest RS in all countries. Period estimates of 5-year RS were 94-95% in age 55 years and 84-89% in age 75 years, while 10-year RS were 88-91% in age 55 years and 69-84% in age 75 years. Women aged 40 years lost on average 11.0-13.8 years, while women lost 3.8-6.0 years if aged 55 and 1.9-3.5 years if aged 75 years. CONCLUSIONS: Survival for Nordic women with breast cancer improved from 1990 to 2016 in all age groups, albeit with larger country variation among older women where survival was also lower. Women over 70 years of age have not had the same survival improvement as women of younger age.

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.

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.

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.

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.

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.

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.

Trends in cancer survival in the Nordic countries 1990-2016: the NORDCAN survival studies.

BACKGROUND: Differences in cancer survival between the Nordic countries have previously been reported. The aim of this study was to examine whether these differences in outcome remain, based on updated information from five national cancer registers. MATERIALS AND METHODS: The data used for the analysis was from the NORDCAN database focusing on nine common cancers diagnosed 1990-2016 in Denmark, Finland, Iceland, Norway and Sweden with maximum follow-up through 2017. Relative survival (RS) was estimated at 1 and 5 years using flexible parametric RS models, and percentage point differences between the earliest and latest years available were calculated. RESULTS: A consistent improvement in both 1- and 5-year RS was found for most studied sites across all countries. Previously observed differences between the countries have been attenuated. The improvements were particularly pronounced in Denmark that now has cancer survival similar to the other Nordic countries. CONCLUSION: The reasons for the observed improvements in cancer survival are likely multifactorial, including earlier diagnosis, improved treatment options, implementation of national cancer plans, uniform national cancer care guidelines and standardized patient pathways. The previous survival disadvantage in Denmark is no longer present for most sites. Continuous monitoring of cancer survival is of importance to assess the impact of changes in policies and the effectiveness of health care systems.

Progress in cancer survival, mortality, and incidence in seven high-income countries 1995-2014 (ICBP SURVMARK-2): a population-based study.

BACKGROUND: Population-based cancer survival estimates provide valuable insights into the effectiveness of cancer services and can reflect the prospects of cure. As part of the second phase of the International Cancer Benchmarking Partnership (ICBP), the Cancer Survival in High-Income Countries (SURVMARK-2) project aims to provide a comprehensive overview of cancer survival across seven high-income countries and a comparative assessment of corresponding incidence and mortality trends. METHODS: In this longitudinal, population-based study, we collected patient-level data on 3·9 million patients with cancer from population-based cancer registries in 21 jurisdictions in seven countries (Australia, Canada, Denmark, Ireland, New Zealand, Norway, and the UK) for seven sites of cancer (oesophagus, stomach, colon, rectum, pancreas, lung, and ovary) diagnosed between 1995 and 2014, and followed up until Dec 31, 2015. We calculated age-standardised net survival at 1 year and 5 years after diagnosis by site, age group, and period of diagnosis. We mapped changes in incidence and mortality to changes in survival to assess progress in cancer control. FINDINGS: In 19 eligible jurisdictions, 3 764 543 cases of cancer were eligible for inclusion in the study. In the 19 included jurisdictions, over 1995-2014, 1-year and 5-year net survival increased in each country across almost all cancer types, with, for example, 5-year rectal cancer survival increasing more than 13 percentage points in Denmark, Ireland, and the UK. For 2010-14, survival was generally higher in Australia, Canada, and Norway than in New Zealand, Denmark, Ireland, and the UK. Over the study period, larger survival improvements were observed for patients younger than 75 years at diagnosis than those aged 75 years and older, and notably for cancers with a poor prognosis (ie, oesophagus, stomach, pancreas, and lung). Progress in cancer control (ie, increased survival, decreased mortality and incidence) over the study period was evident for stomach, colon, lung (in males), and ovarian cancer. INTERPRETATION: The joint evaluation of trends in incidence, mortality, and survival indicated progress in four of the seven studied cancers. Cancer survival continues to increase across high-income countries; however, international disparities persist. While truly valid comparisons require differences in registration practice, classification, and coding to be minimal, stage of disease at diagnosis, timely access to effective treatment, and the extent of comorbidity are likely the main determinants of patient outcomes. Future studies are needed to assess the impact of these factors to further our understanding of international disparities in cancer survival. FUNDING: Canadian Partnership Against Cancer; Cancer Council Victoria; Cancer Institute New South Wales; Cancer Research UK; Danish Cancer Society; National Cancer Registry Ireland; The Cancer Society of New Zealand; National Health Service England; Norwegian Cancer Society; Public Health Agency Northern Ireland, on behalf of the Northern Ireland Cancer Registry; The Scottish Government; Western Australia Department of Health; and Wales Cancer Network.

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.

Skin cancer projections and cost savings 2014-2045 of improvements to the Danish sunbed legislation of 2014.

BACKGROUND: Sunbed use increases the risk of skin cancer. The Danish sunbed legislation (2014) did not include an age limit. AIM: To model skin cancer incidences and saved costs from potential effects of structural interventions on prevalence of sunbed use. MATERIALS AND METHODS: Survey data from 2015 were collected for 3999 Danes, representative for the Danish population in regards to age, gender and region. Skin cancer incidences were modelled in the Prevent program, using population projections, historic cancer incidence, sunbed use exposure and relative risk of sunbed use on melanoma. RESULTS: If structural interventions like an age limit of 18 years for sunbed use or complete ban had been included in the Danish sunbed legislation in 2014, it would have reduced the annual number of skin cancer cases with 455 or 4177, respectively, while for the entire period, 2014-2045 the total reductions would be 3730 or 81 887 fewer cases, respectively. The cost savings from an age limit or ban, respectively, are 9 and 129 millions € during 2014-2045. CONCLUSION: Legislative restrictive measures which could reduce the sunbed use exists. Danish politicians have the opportunity, supported by the population, to reduce the skin cancer incidence and thereby to reduce the future costs of skin cancer.

Nordic Cancer Registries - an overview of their procedures and data comparability.

BACKGROUND: The Nordic Cancer Registries are among the oldest population-based registries in the world, with more than 60 years of complete coverage of what is now a combined population of 26 million. However, despite being the source of a substantial number of studies, there is no published paper comparing the different registries. Therefore, we did a systematic review to identify similarities and dissimilarities of the Nordic Cancer Registries, which could possibly explain some of the differences in cancer incidence rates across these countries. METHODS: We describe and compare here the core characteristics of each of the Nordic Cancer Registries: (i) data sources; (ii) registered disease entities and deviations from IARC multiple cancer coding rules; (iii) variables and related coding systems. Major changes over time are described and discussed. RESULTS: All Nordic Cancer Registries represent a high quality standard in terms of completeness and accuracy of the registered data. CONCLUSIONS: Even though the information in the Nordic Cancer Registries in general can be considered more similar than any other collection of data from five different countries, there are numerous differences in registration routines, classification systems and inclusion of some tumors. These differences are important to be aware of when comparing time trends in the Nordic countries.

Cancer risks after solid organ transplantation and after long-term dialysis.

Immunosuppression involves an inability to control virus infections and increased incidence of virus-associated cancers. Some cancers without known viral etiology are also increased, but data on exactly which cancer forms are increased has been inconsistent. To provide a reliable and generalizable estimate, with high statistical power and long follow-up time, we assessed cancer risks using comprehensive, population-based registries in two different countries and from two different immunosuppressed patient groups (solid organ transplant recipients (OTRs) and long-term dialysis patients (LDPs)). National registries in Denmark and Sweden identified 20,804 OTRs and 31,140 LDPs that were followed up using national cancer registries. Standardized incidence ratios (SIR) compared to the general population were estimated. We found highly similar results, both for the two different countries and for the two different immunosuppressed cohorts, namely an increased incidence for the following specific cancer forms: Non-melanoma skin cancer (NMSC), non-Hodgkin's lymphoma and cancers of the lip, kidney, larynx and thyroid. The SIR for overall cancer among OTRs was 3.5 [n = 2,142, 95% CI, 3.4-3.7] in Sweden, 2.9 [n = 1,110, 95% CI, 2.8-3.1] in Denmark and 1.6 [n = 1,713, 95% CI, 1.5-1.6] among LDP. The SIR for NMSC among OTRs was 44.7 [n = 994, 95% CI, 42-47.5] in Sweden and 41.5 [n = 445, 95% CI, 37.8-45.5] in Denmark. The increased SIR for NMSC among LDPs was 5.3 [n = 304, 95% CI, 4.7-5.9]). In summary, an increased SIR for a specific, similar set of cancer forms is consistently found among the immunosuppressed. Conceivable explanations include surveillance bias and immunosuppression-related susceptibility to viral infections.

Comparison of non-parametric methods for ungrouping coarsely aggregated data.

BACKGROUND: Histograms are a common tool to estimate densities non-parametrically. They are extensively encountered in health sciences to summarize data in a compact format. Examples are age-specific distributions of death or onset of diseases grouped in 5-years age classes with an open-ended age group at the highest ages. When histogram intervals are too coarse, information is lost and comparison between histograms with different boundaries is arduous. In these cases it is useful to estimate detailed distributions from grouped data. METHODS: From an extensive literature search we identify five methods for ungrouping count data. We compare the performance of two spline interpolation methods, two kernel density estimators and a penalized composite link model first via a simulation study and then with empirical data obtained from the NORDCAN Database. All methods analyzed can be used to estimate differently shaped distributions; can handle unequal interval length; and allow stretches of 0 counts. RESULTS: The methods show similar performance when the grouping scheme is relatively narrow, i.e. 5-years age classes. With coarser age intervals, i.e. in the presence of open-ended age groups, the penalized composite link model performs the best. CONCLUSION: We give an overview and test different methods to estimate detailed distributions from grouped count data. Health researchers can benefit from these versatile methods, which are ready for use in the statistical software R. We recommend using the penalized composite link model when data are grouped in wide age classes.