Mathieu Laversanne

Global patterns and trends in colorectal cancer incidence and mortality

Objective The global burden of colorectal cancer (CRC) is expected to increase by 60% to more than 2.2 million new cases and 1.1 million deaths by 2030. In this study, we aim to describe the recent CRC incidence and mortality patterns and trends linking the findings to the prospects of reducing the burden through cancer prevention and care. Design Estimates of sex-specific CRC incidence and mortality rates in 2012 were extracted from the GLOBOCAN database. Temporal patterns were assessed for 37 countries using data from Cancer Incidence in Five Continents (CI5) volumes I–X and the WHO mortality database. Trends were assessed via the annual percentage change using joinpoint regression and discussed in relation to human development levels. Results CRC incidence and mortality rates vary up to 10-fold worldwide, with distinct gradients across human development levels, pointing towards widening disparities and an increasing burden in countries in transition. Generally, CRC incidence and mortality rates are still rising rapidly in many low-income and middle-income countries; stabilising or decreasing trends tend to be seen in highly developed countries where rates remain among the highest in the world. Conclusions Patterns and trends in CRC incidence and mortality correlate with present human development levels and their incremental changes might reflect the adoption of more western lifestyles. Targeted resource-dependent interventions, including primary prevention in low-income, supplemented with early detection in high-income settings, are needed to reduce the number of patients with CRC in future decades.

International Variations and Trends in Renal Cell Carcinoma Incidence and Mortality

CONTEXT Renal cell carcinoma (RCC) incidence rates are higher in developed countries, where up to half of the cases are discovered incidentally. Declining mortality trends have been reported in highly developed countries since the 1990s. OBJECTIVE To compare and interpret geographic variations and trends in the incidence and mortality of RCC worldwide in the context of controlling the future disease burden. EVIDENCE ACQUISITION We used data from GLOBOCAN, the Cancer Incidence in Five Continents series, and the World Health Organisation mortality database to compare incidence and mortality rates in more than 40 countries worldwide. We analysed incidence and mortality trends in the last 10 yr using joinpoint analyses of the age-standardised rates (ASRs). EVIDENCE SYNTHESIS RCC incidence in men varied in ASRs (World standard population) from approximately 1/100,000 in African countries to >15/100,000 in several Northern and Eastern European countries and among US blacks. Similar patterns were observed for women, although incidence rates were commonly half of those for men. Incidence rates are increasing in most countries, most prominently in Latin America. Although recent mortality trends are stable in many countries, significant declines were observed in Western and Northern Europe, the USA, and Australia. Southern European men appear to have the least favourable RCC mortality trends. CONCLUSIONS Although RCC incidence is still increasing in most countries, stabilisation of mortality trends has been achieved in many highly developed countries. There are marked absolute differences and opposing RCC mortality trends in countries categorised as areas of higher versus lower human development, and these gaps appear to be widening. PATIENT SUMMARY Renal cell cancer is becoming more commonly diagnosed worldwide in both men and women. Mortality is decreasing in the most developed settings, but not in low- and middle-income countries, where access to and the availability of optimal therapies are likely to be limited.

Cancer Incidence in Five Continents: Inclusion criteria, highlights from Volume X and the global status of cancer registration

Cancer Incidence in Five Continents (CI5), a longstanding collaboration between the International Agency for Research on Cancer and the International Association of Cancer Registries, serves as a unique source of cancer incidence data from high‐quality population‐based cancer registries around the world. The recent publication of Volume X comprises cancer incidence data from 290 registries covering 424 populations in 68 countries for the registration period 2003–2007. In this article, we assess the status of population‐based cancer registries worldwide, describe the techniques used in CI5 to evaluate their quality and highlight the notable variation in the incidence rates of selected cancers contained within Volume X of CI5. We also discuss the Global Initiative for Cancer Registry Development as an international partnership that aims to reduce the disparities in availability of cancer incidence data for cancer control action, particularly in economically transitioning countries, already experiencing a rapid rise in the number of cancer patients annually.

The Impact of Diagnostic Changes on the Rise in Thyroid Cancer Incidence: A Population-Based Study in Selected High-Resource Countries

BACKGROUND Thyroid cancer (TC) incidence is rising in many countries, but the corresponding mortality is constant or declining. Incidence increases appear largely restricted to small papillary TC in young/middle-age individuals. We compared age-specific incidence rates across countries and time periods in order to estimate the fraction of TC possibly attributable to increased surveillance of the thyroid gland (diagnostic changes) following the introduction of neck ultrasonography in the 1980s. METHODS We focused on high-resource countries, including four Nordic countries, England and Scotland, France, Italy, the United States, Australia, Japan, and the Republic of Korea. Before the 1970s, TC incidence in Nordic countries increased proportionally to the second power of age, consistent with the multistage model of carcinogenesis. Using this historical observation for reference, we attributed the progressive departure from linearity of the age curves in each country to an increased detection of asymptomatic disease in young/middle-age individuals. The proportion of cases attributable to diagnostic changes was estimated from the difference between observed rates and those expected using the Nordic countries as reference. RESULTS Diagnostic changes may account for ≥60% of TC cases diagnosed in 2003-2007 in women aged under 80 years in France, Italy, the United States, Australia, and the Republic of Korea, and approximately 50% in other assessed countries, except Japan (30%). The proportions attributable to diagnostic changes were higher in countries with largest incidence increases and were consistent across sexes, although increases were smaller and delayed in men. CONCLUSIONS A large proportion of TC cases diagnosed in high-resource countries in the last two decades are likely to be due to diagnostic changes. This proportion has progressively increased over time, and it is likely to grow further in the future. Since there is evidence of harm but no proof of benefit from the intense scrutiny of the thyroid, the dangers of overdiagnosis and overtreatment of TC should be urgently addressed.

International trends in liver cancer incidence, overall and by histologic subtype, 1978–2007

Primary liver cancer, the most common histologic types of which are hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), is the second leading cause of cancer death worldwide. While rising incidence of liver cancer in low‐risk areas and decreasing incidence in some high‐risk areas has been reported, trends have not been thoroughly explored by country or by histologic type. We examined liver cancer incidence overall and by histology by calendar time and birth cohort for selected countries between 1978 and 2007. For each successive 5‐year period, age‐standardized incidence rates were calculated from volumes V‐IX of the Cancer Incidence in Five Continents electronic database (CI5plus) and the newly released CI5X (volume X) database. Wide global variations persist in liver cancer incidence. Rates of liver cancer remain highest in Asian countries, specifically Eastern and South‐Eastern Asian countries. While rates in most of these high‐risk countries have been decreasing in recent years, rates in India and several low‐risk countries of Africa, Europe, the Americas, and Oceania have been on the rise. Liver cancer rates by histologic type tend to convey a similar temporal profile. However, in Thailand, France, and Italy, ICC rates have increased while HCC rates have declined. We expect rates in high‐risk countries to continue to decrease, as the population seroprevalence of hepatitis B virus (HBV) continues to decline. In low‐risk countries, targeted screening and treatment of the hepatitis C virus (HCV), treatment of diabetes and primary prevention of obesity, will be key in reducing future liver cancer incidence.

Prostate cancer incidence in 43 populations worldwide: An analysis of time trends overall and by age group.

Prostate cancer is a significant public health burden and a major cause of morbidity and mortality among men worldwide. Analyzing geographic patterns and temporal trends may help identify high‐risk populations, suggest the degree of PSA testing, and provide clues to etiology. We used incidence data available from the International Agency for Research on Cancer (IARC) and certain cancer registries for 43 populations across five continents during a median period of 24 years. Trends in overall prostate cancer rates showed five distinct patterns ranging from generally monotonic increases to peaking of rates followed by declines, which coincide somewhat with changes in the prevalence of PSA testing. Trends in age‐specific rates generally mirrored those in the overall rates, with several notable exceptions. For populations where overall rates increased rapidly and then peaked, exemplified in North America and Oceania, the highest incidence tended to be most pronounced and occurred during earlier calendar years among older men compared with younger ones. For populations with almost continual increases in overall rates, exemplified in Eastern Europe and Asia, peaks were evident among men aged ≥75 years in many instances. Rates for ages 45–54 years did not clearly stabilize or decline in the majority of studied populations. Global geographic variation remained substantial for both overall and age‐specific incidence rates regardless of levels of PSA testing, with the lowest rates consistently in Asia. Explanations for the persistent geographic differences and the continuing increases of especially early‐onset prostate cancer remain unclear.

Predicting the Future Burden of Esophageal Cancer by Histological Subtype: International Trends in Incidence up to 2030

Objectives:Rapid increases in the incidence of esophageal adenocarcinoma (EAC) in high-income countries in the past decades have raised public health concerns. This study is the first to predict the future burden of esophageal cancer by histological subtype using international incidence data.Methods:Data on esophageal cancer incidence by year of diagnosis, sex, histology, and age group were extracted from 42 registries in 12 countries included in the last three volumes (VIII–X) of Cancer Incidence in Five Continents, contributing at least 15 years of consecutive data. Numbers of new cases and incidence rates were predicted up to 2030 by fitting and extrapolating age–period–cohort models; the differential impact of demographic vs. risk changes on future cases were examined.Results:The number of new AC cases is expected to increase rapidly 2005–2030 in all studied countries as a combined result of increasing risk and changing demographics. In contrast, the incidence of esophageal squamous cell carcinoma (ESCC) is predicted to continue decreasing in most countries. By 2030, 1 in 100 men in the Netherlands and the United Kingdom are predicted to be diagnosed with EAC during their lifetime.Conclusions:The burden from EAC is expected to rise dramatically across high-income countries and has already or will surpass ESCC incidence in the coming years, especially among men. Notwithstanding the inherent uncertainties in trend-based predictions and in subtype misclassification, these findings highlight an ongoing transition in the epidemiology of esophageal cancer that is highly relevant to future cancer control planning and clinical practice.

International testicular cancer incidence trends: generational transitions in 38 countries 1900–1990

PurposeRapid increases in testicular cancer incidence have marked the second half of the last century. While these secular rises, observed mainly in countries attaining the highest levels of human development, appear to have attenuated in the last decade, rates continue to increase in countries transiting toward high developmental levels. The purpose of our study was to provide a comprehensive analysis and presentation of the cohort-specific trends in testicular cancer incidence rates in 38 countries worldwide.MethodsWe used an augmented version of the Cancer Incidence in Five Continents series to analyze testicular cancer incidence in men aged 15–54 in 38 countries, via age–period–cohort analysis.ResultsIn many European countries, the USA, Canada, Australia, and New Zealand, there is a continuation of the increasing risk among successive generations, yet rates are attenuating in male cohorts born since the 1970s in several Northern European countries, in contrast to the steeply increasing trends in recent cohorts in Southern Europe. Incidence rates have also been increasing in the populations traditionally at rather low risk, such as in the Philippines, Singapore, China, and Costa Rica.ConclusionsThe attenuation of testicular cancer risk in younger generations (in the most developed countries) alongside concomitant increases (in countries undergoing developmental change) is indicative of a global transition in the risk of testicular cancer. While identifying the underlying causes remains a major challenge, increasing awareness and adapting national healthcare systems to accommodate a growing burden of testicular cancer may prevent future avoidable deaths in young men.

Cervical cancer in Africa, Latin America and the Caribbean, and Asia: Regional inequalities and changing trends

The vast majority (86% or 453,000 cases) of the global burden of cervical cancer occurs in Africa, Latin America and the Caribbean and Asia, where one in nine new cancer cases are of the cervix. Although the disease has become rare in high‐resource settings (e.g., in North America, parts of Europe, Japan) that have historically invested in effective screening programs, the patterns and trends are variable elsewhere. While favourable incidence trends have been recorded in many populations in Asia and Latin America and the Caribbean in the past decades, rising rates have been observed in sub‐Saharan African countries, where high quality incidence series are available. The challenge for countries heavily affected by the disease in these regions is to ensure resource‐dependent programmes of screening and vaccination are implemented to transform the situation, so that accelerated declines in cervical cancer are not the preserve of high‐income countries, but become the norm in all populations worldwide.

Cancer patterns and trends in Central and South America

RATIONALE AND OBJECTIVE Cancer burden is increasing in Central and South America (CSA). We describe the current burden of cancer in CSA. METHODS We obtained regional and national-level cancer incidence data from 48 population-based registries (13 countries) and nation-wide cancer mortality data from the WHO (18 countries). We estimated world population age-standardized incidence and mortality rates per 100,000 person-years. RESULTS The leading cancers diagnosed were prostate, lung, breast, cervix, colorectal, and stomach, which were also the primary causes of cancer mortality. Countries of high/very high human development index (HDI) in the region experienced a high burden of prostate and breast cancer while medium HDI countries had a high burden of stomach and cervical cancers. Between countries, incidence and mortality from all cancers combined varied by 2-3-fold. French Guyana, Brazil, Uruguay, and Argentina had the highest incidence of all cancers while Uruguay, Cuba, Argentina, and Chile had the highest mortality. Incidence of colorectum, prostate and thyroid cancers increased in Argentina, Brazil, Chile and Costa Rica from 1997 to 2008, while lung, stomach and cervical cancers decreased. CONCLUSION CSA carries a double-burden of cancer, with elevated rates of infection- and lifestyle-related cancers. Encountered variation in cancer rates between countries may reflect differences in registration practices, healthcare access, and public awareness. Resource-dependent interventions to prevent, early diagnose, and treat cancer remain an urgent priority. There is an overwhelming need to improve the quality and coverage of cancer registration to guide and evaluate future cancer control policies and programs.