World Cancer Report

(1)

Cancer research for cancer prevention

Edited by CHRISTOPHER P. WILD,

ELISABETE WEIDERPASS, and BERNARD W. STEWART

World Cancer

Report

(2)

Edited by CHRISTOPHER P. WILD,

ELISABETE WEIDERPASS, and BERNARD W. STEWART

LYON, 2020

World Cancer Report

Cancer research

for cancer prevention

(3)

Some rights reserved. This work is available under the Creative Commons Attribution-NonCommercial-NoDerivs 3.0 IGO licence (CC BY-NC-ND 3.0 IGO; https://creativecommons.org/licenses/by-nc-nd/3.0/igo/).

Under the terms of this licence, you may copy and redistribute the work for non-commercial purposes, provided the work is appropriately cited, as indicated below. In any use of this work, there should be no suggestion that WHO endorses any specific organization, products or services. The use of the WHO logo is not permitted.

Any mediation relating to disputes arising under the licence shall be conducted in accordance with the mediation rules of the World Intellectual Property Organization.

Suggested citation.

Wild CP, Weiderpass E, Stewart BW, editors (2020). World Cancer Report: Cancer Research for Cancer Prevention. Lyon, France: International Agency for Research on Cancer. Available from: http://publications.iarc.fr/586. Licence: CC BY-NC-ND 3.0 IGO.

Sales, rights and permissions.

To purchase print copies distributed by WHO Press, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland, see http://apps.who.int/bookorders. Tel.: +41 22 791 3264; Fax: +41 22 791 4857; email: [email protected].

To purchase IARC publications in electronic format, see the IARC Publications website (http://publications.iarc.fr).

To submit requests for adaptations or commercial use and queries on rights and licensing, see the IARC Publications website (http://publications.iarc.fr/Rights-And-Permissions).

Third-party materials.

If you wish to reuse material from this work that is attributed to a third party, such as tables, figures or images, it is your responsibility to determine whether permission is needed for that reuse and to obtain permission from the copyright holder. The risk of claims resulting from infringement of any third-party-owned component in the work rests solely with the user.

General disclaimers.

The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of WHO or contributing agencies concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted and dashed lines on maps represent approximate border lines for which there may not yet be full agreement.

The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommend- ed by WHO or contributing agencies in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters.

All reasonable precautions have been taken by WHO to verify the information contained in this publication. However, the published material is being distributed without warranty of any kind, either expressed or implied. The responsibility for the interpreta- tion and use of the material lies with the reader. In no event shall WHO or contributing agencies be liable for damages arising from its use.

Cover images, from top to bottom: Photomicrograph of retinoblastoma (Credit: Ralph C. Eagle, Jr, MD, Department of Pathology, Wills Eye Hospital, Philadelphia, Pennsylvania, USA). A woman undergoes a computed tomography scan (Credit: T2 Images/

Getty Images). A waiter in a hoteli (tearoom) pours scalding hot milky tea for customers in Nyaru, a settlement at the edge of the Rift Valley in Kenya; IARC and Moi University are investigating the high rates of oesophageal cancer in Kenya and have found that consumption of hot tea is implicated (Credit: Daniel Middleton/IARC). Storage of biological samples in the IARC Biobank (Credit: Morena Sarzo/IARC). A girl receives a human papillomavirus (HPV) vaccination; in Pune district in Maharashtra, India, IARC is working closely with national institutions to evaluate the efficacy of fewer than three doses of HPV vaccine in protect- ing women against cervical cancer (Credit: Morena Sarzo/IARC). Background image: The Blue Marble: Next Generation is a mosaic of satellite data taken mostly from a NASA sensor called the Moderate Resolution Imaging Spectroradiometer (MODIS) that flies aboard NASA’s Terra and Aqua satellites (Credit: NASA/Goddard Space Flight Center/Reto Stöckli).

IARC Library Cataloguing in Publication Data

Names: Wild, Christopher P., editor. | Weiderpass, Elisabete, editor. | Stewart, Bernard W., editor.

Title: World cancer report: cancer research for cancer prevention / edited by Christopher P. Wild, Elisabete Weiderpass, Bernard W. Stewart.

Other titles: World cancer report 2020.

Description: Lyon: International Agency for Research on Cancer, 2020. | Includes bibliographical references and index.

Identifiers: ISBN 978-92-832-0447-3 (pbk.) | ISBN 978-92-832-0448-0 (ebook)

(4)

Editors Christopher P. Wild Elisabete Weiderpass Bernard W. Stewart

Associate Editors Ian Cree

Jacques Ferlay Kurt Straif

Managing Editors Nicolas Gaudin

Teresa Lee

English Editor Karen Müller

Project Manager Sylvia Lesage

Production Assistant Freya Damrell

Layout http://messaggio.ch

Printing Imprimerie Faurite, France

World Cancer Report

Cancer research for cancer prevention

(5)

Christian C. Abnet Clement A. Adebamowo Demetrius Albanes Laia Alemany Vilches Maribel Almonte

Devasena Anantharaman Annie S. Anderson Benjamin O. Anderson Bruce K. Armstrong Patricia Ashton-Prolla Dagfinn Aune

Anssi Auvinen Anna Babayan Chunxue Bai

Rosamonde E. Banks Partha Basu

Linda Bauld Iacopo Baussano Laura E. Beane Freeman Sonja I. Berndt

Margherita Bignami Maria Blettner Ron Borland Freddie Bray Paul Brennan Louise A. Brinton Jennifer D. Brooks Julia Brotherton Karen Brown Laia Bruni Nele Brusselaers

Christopher Bullen Gloria M. Calaf Karen Canfell Bochen Cao Franco Cavalli Stephen J. Chanock Isabelle Chemin Chien-Jen Chen Wanqing Chen Zhengming Chen Zvavahera Mike Chirenje Vincent J. Cogliano Aaron J. Cohen Graham A. Colditz Pietro Comba David I. Conway Ian A. Cree Jack Cuzick Luigino Dal Maso Diona L. Damian Robert D. Daniels George Davey Smith Louise Davies Sanford M. Dawsey Harry J. de Koning Catherine de Martel Lynette Denny Carol E. DeSantis Joanna Didkowska Eugenia Dogliotti Laure Dossus

Ronny Drapkin Eric J. Duell

Karin Ekström Smedby A. Heather Eliassen Steffen Emmert Karen M. Emmons Carolina Espina Jessica N. Everett Veronika Fedirko Ian S. Fentiman Jacques Ferlay Pietro Ferrari

Miranda M. Fidler-Benaoudia James Flanagan

Leandro Fórnias Machado de Rezende

Silvia Franceschi David O. Francis Neal D. Freedman Christine M. Friedenreich Peter P. Fu

Koraljka Gall Trošelj Judy E. Garber Gail Garvey Gemma Gatta Cindy L. Gauvreau Adi F. Gazdar (deceased) Ophira Ginsburg

Edward L. Giovannucci Rüdiger Greinert John D. Groopman Giuseppe Grosso

Contributors

(6)

Marc Gunter Jason Gurney Kathryn Z. Guyton

Bothwell Takaingofa Guzha Janet Hall

Susan E. Hankinson Zdenko Herceg Rolando Herrero Rayjean J. Hung David J. Hunter Ivano Iavarone André M. Ilbawi Lisa Iversen

Charles W. Jameson Dorota Jarosińska Mazda Jenab Mattias Johansson Michael E. Jones Shaoqing Ju Rudolf Kaaks Sakari Karjalainen Ausrele Kesminiene Timothy J. Key Malcolm King Manolis Kogevinas Anita Koushik James R. Krycer Alan Prem Kumar Kunjan Kunjan Carlo La Vecchia Dirk W. Lachenmeier

Marc Ladanyi

Béatrice Lauby-Secretan Dominique Laurier C. René Leemans Michael Leitzmann Sarah Lewis Donghui Li He Li Terry Lichtor Martha S. Linet Johan P. Mackenbach Núria Malats

Reza Malekzadeh Mohandas K. Mallath Alberto Mantovani Richard M. Martin John D. Mathews Valerie McCormack Marjorie L. McCullough James McKay

Francis Mégraud Filip Meheus Ronald L. Melnick Wenbo Meng

Dominique S. Michaud David J. Miller

Steven C. Moore Colin R. Muirhead Raúl Murillo Robert Newton Chikako Nishigori

Joëlle L. Nortier Josiah Ochieng Hiroko Ohgaki Klaus Pantel Alexander Parker Electra D. Paskett Julietta Patnick Graham Pawelec Neil Pearce David H. Phillips

Sydney E. Philpott-Streiff Martyn Plummer

Igor Pogribny Kornelia Polyak

Nagarajan Rajendra Prasad Liang Qiao

You-Lin Qiao

Ewa Rajpert-De Meyts Kunnambath Ramadas Timothy R. Rebbeck Srinath K. Reddy Jürgen Rehm Natalie Reimers Sabina Rinaldi Bridget H. Robson Eve Roman Martin Röösli Thierry Roumeguère Esther Roura Fornells Anja Rudolph

Lesley Rushton

(7)

Aoife Ryan

Rengaswamy Sankaranarayanan Diana Sarfati

Catherine Sauvaget Augustin Scalbert Ghislaine Scelo David Schottenfeld

Mary K. Schubauer-Berigan Wolfgang A. Schulz

Joachim Schüz Nereo Segnan Carlo Senore Gautam Sethi

Muthu K. Shanmugam Tatsuhiro Shibata Kevin D. Shield Jack Siemiatycki Diane M. Simeone Colinda Simons Niels E. Skakkebæk

Alexandra G. Smith Martyn T. Smith Robert A. Smith Isabelle Soerjomataram Aswathy Sreedevi Bernard W. Stewart Kurt Straif

Michael J. Thun Herbert Tilg

Massimo Tommasino Steinar Tretli

Ioannis P. Trougakos Michelle C. Turner Renée Turzanski Fortner Giske Ursin

Toshikazu Ushijima Salvatore Vaccarella Piet van den Brandt Mieke Van Hemelrijck Katherine Van Loon

Christine Varon Paolo Vineis Elizabeth Ward Penelope M. Webb Elisabete Weiderpass Jeffrey N. Weitzel Elizabeth A. Whelan David Whiteman Christopher P. Wild Walter C. Willett Martin J. Wiseman Diana R. Withrow Zhixun Yang Jiri Zavadil Georg Zeller Ariana Znaor

For a complete list of contributors and their affiliations, see pages 573–581.

(8)

Foreword Preface Introduction

1 The global cancer burden

1.1 The burden and prevention of premature deaths from noncommunicable diseases, including cancer: a global perspective 1.2 Global trends in cancer incidence

and mortality

1.3 Transitions in human development and the global cancer burden

Known causes of human cancer by organ site 2 Causes of cancer, including

hazardous circumstances 2.1 Tobacco products

Massive and still growing causes of cancer worldwide

2.2 Infectious agents

Missed opportunities for prevention 2.3 Alcohol consumption

A leading risk factor for cancer 2.4 Sunlight and ultraviolet radiation

Affecting skin cancer incidence in many countries 2.5 Ionizing radiation and radiofrequency

electromagnetic fields

Further clarification of particular risks 2.6 Diet and nutrition

Understanding which factors are critical 2.7 Physical activity, sedentary behaviour,

and obesity

Established and emerging modifiable risk factors 2.8 Dietary carcinogens

A continuing concern in various contexts 2.9 Contamination of air, water, soil, and food

The challenge is to characterize specific risks 2.10 Occupation

The need for continuing vigilance 2.11 Pharmaceutical drugs

A current focus on hormones

World Cancer Research Fund International/

American Institute for Cancer Research

At the United Nations General Assembly in 2018, world leaders agreed to take responsibility for preventing and treating cancer and other noncommunicable diseases, including fiscal measures to protect people from cancer- causing products, to promote evidence-based treatment, and to work towards universal health coverage.

We have no time to lose. The cancer burden is rising globally – but not equally. The greatest impact of cancer and the fastest increase in the cancer burden over the coming decades is projected to be in low- and middle-income countries, many of which already face difficulties coping with the current burden. There are massive social inequalities in cancer, with large variations in incidence, survival, and mortality between social groups.

We have learned that many cancer cases can be prevented, and even when prevention is not possible, early diagnosis saves lives. By using evidence-based and feasible interventions and adapting them to low- and middle- income countries where most new cancer cases will occur, a large proportion of those cases can be prevented.

There is much that can be done to reduce social inequalities in cancer globally.

Robust, independent scientific evidence is critical, focused on the scale and patterns of cancer and its causes, prevention, and early detection. The high-quality research produced by the International Agency for Research on Cancer (IARC), working with researchers around the world, is essential for the development of evidence-based guidelines and policy by WHO, and for regulatory decisions by national institutions to protect the health of their populations.

This new IARC World Cancer Report presents the most comprehensive, up-to-date science on cancer prevention, including statistics, causes, and mechanisms, and how this can be used to implement effective, resource- appropriate strategies for cancer prevention and early detection. It also includes examples of successful prevention strategies. This book is a useful reference for researchers, cancer professionals, public health workers, and policy-makers.

The 2017 World Health Assembly requested WHO, in collaboration with IARC, to provide a global perspective on all measures that are recognized to limit the burden of cancer. The outcome of this charge – the WHO Report on Cancer: Setting priorities, investing wisely and providing care for all – complements the IARC World Cancer Report by synthesizing evidence to translate the latest knowledge into actionable policies to support govern- ments. These two publications provide a solid foundation for effective cancer policies, and bring us closer to our goal of changing the trajectory of cancer for communities around the world.

Dr Tedros Adhanom Ghebreyesus Director-General

World Health Organization

Foreword

(11)

The objective of the International Agency for Research on Cancer (IARC) is to promote international collaboration in cancer research. The Agency is interdisciplinary, bringing together skills in epidemiology, laboratory sciences, and biostatistics to identify the causes of cancer so that preventive measures may be adopted and the burden of disease and associated suffering reduced. A significant feature of IARC is its expertise in coordinating research across countries and organizations; its independent role as an international organization facilitates this activity.

As part of its wide dissemination of information about cancer, the Agency produces World Cancer Report.

The previous World Cancer Report, published in 2014, identified a foreseeable increase in the global burden of cancer, with a particularly heavy burden projected to fall on low- and middle-income countries. This new World Cancer Report is focused on the only consideration that will credibly decrease that burden: prevention. This vol- ume addresses cancer research for cancer prevention.

IARC routinely coordinates specialist assessments in which multiple individual research studies – typically hundreds or thousands of articles – are assessed by international groups of expert scientists. The results are published as volumes of publications series, and each series is widely recognized as providing authoritative determinations. These series include the IARC Monographs on the Identification of Carcinogenic Hazards to Humans, which address the causes of cancer; the volumes of Cancer Incidence in Five Continents, which present population-based data on cancer occurrence; the IARC Handbooks of Cancer Prevention, which evaluate cancer prevention strategies; and the WHO Classification of Tumours series (also known as the WHO Blue Books), for the histological and genetic classification of human tumours. Typically, a particular volume in each of these series is focused on some aspect of cancer causation, prevention, pathology, and so on. This approach is not amenable to the provision of broad perspectives.

For broad perspectives, World Cancer Report is the relevant publication. World Cancer Report is not a digest of assessments made by IARC or any other authority. World Cancer Report is based on purpose-made assessments, prepared by recognized investigators worldwide and published after undergoing peer review.

A broad perspective – and, where possible, a “bottom line” – is crucial in several respects. First, it ensures that all relevant findings are taken into account. For example, for ultraviolet radiation in sunlight, evidence of tissue injury from low-level exposure must be considered together with known biological benefits, including production of vita- min D. Second, although knowledge of biological mechanisms provides valuable insights, it may not necessarily account for human circumstances. For example, in preventing exposures to known human carcinogens, inequalities between populations may contribute to marked variations in health outcomes. Third, although investigative design may be constrained to parameters that can be readily determined, human behaviour is never restricted in such a way. For example, the incidence of obesity-related cancers is critically affected by dietary composition, physical activity, and sedentary practices, because these vary between communities. Finally, factors that influence cancer causation and prevention may have markedly different outcomes when implemented across communities or countries that differ environmentally, sociologically, climatically, and economically.

Preface

(12)

World Cancer Report xi IARC is uniquely placed to encompass a broad spectrum of knowledge while presenting the results in manageable terms. The production of World Cancer Report is achieved by engaging the Agency’s scientific staff to col- laborate in the development of the publication at every level. This includes ensuring that the planned contents address all relevant knowledge; identifying distinguished authors and reviewers from across the globe; ensuring that differing perspectives are offered in a balanced, evidence-based manner; and considering circumstances that my restrict implementation of cancer-preventive interventions.

Cancer can be prevented by avoiding exposure to a known carcinogen. However, this fundamental concept can- not always encompass why different tumour types are particularly prevalent in some populations and not others, or how genomics and related technologies may reveal individual susceptibility and new methods of early diagnosis. Nor can a simplistic understanding of cancer prevention explain why health service-related and other inequalities differentially determine the degree of success of preventive initiatives in different communities. Smoking cessation remains the most widely established means of cancer prevention, and new insights are offered in this World Cancer Report. However, efforts to reduce the burden of cancer cover a broad range, from contending with tumour types that essentially have no known causative agents all the way through to the prospect of cervical cancer being eliminated by the use of vaccines, which have been developed because of research on particular cancer-causing viruses.

Accordingly, this new World Cancer Report provides investigators with detailed information across a multidisciplinary spectrum. Equally, World Cancer Report provides people in the wider community, no matter where they are located worldwide, with insights into how the cancer types that have for so long affected their communities may now have a lesser impact than was previously thought.

Dr Elisabete Weiderpass Director

International Agency for Research on Cancer

(13)

World Cancer Report is an initiative of the International Agency for Research on Cancer (IARC) and is published about every 5 years. Since the inception of World Cancer Report, in 2003, the editorial policy has been to provide a concise, multidisciplinary assessment of current research, made as accessible as possible through a high il- lustrative content and a minimum of scientific jargon. For every chapter included, authority is achieved in the first instance by engaging experts worldwide, who then face the challenge of presenting information covering broad fields in a few thousand words. All chapters are subject to peer review.

The scope of this World Cancer Report

The breadth of knowledge addressed in each World Cancer Report has varied to meet the needs of the time. In 2003, when the availability of concise overviews across all aspects of cancer causation, prevention, and treatment in a single volume was unprecedented, a comprehensive approach was taken. Although a section on cancer treatment was included in the first World Cancer Report, since then there has been an explosive increase in research on precision therapy, and coverage of this proved to be impracticable if World Cancer Report were to remain of manageable size. The fact that World Cancer Report is concise is a central consideration and one that readers collectively value. This may be one reason why World Cancer Report 2014 has been downloaded more than 35 000 times.

As explained in the Preface, this World Cancer Report is focused on cancer research for cancer prevention. This focus has necessitated the inclusion of a new section, so that the scope of available research can be adequately recognized: a section on inequalities that affect cancer prevention. This section has not appeared in any previous World Cancer Report.

Section 4, on inequalities that affect cancer prevention, is the antithesis of, for example, Section 3, on biological processes in cancer development. The chapters in Section 3 concern human biology, largely without reference to geography or community, whereas the chapters that discuss inequalities must involve references to particular communities and their circumstances. The need to address what is particular to various communities also under- pins the content of Section 1, about the global cancer burden.

Another first for this World Cancer Report is the inclusion of a chapter on sporadic cancer. On the basis of current research, an attainable reduction in the incidence of cancer worldwide depends primarily on reducing exposure to known carcinogens. However, currently available research on several cancer types, including prostate cancer, brain cancer, and leukaemias, does not allow a clear proportion of these malignancies to be attributed to particular exogenous factors. So, in such cases, is the development of sporadic cancer due to “bad luck”, and is prevention no longer a consideration? Not at all! Indeed, in such situations particularly, genomics and other technologies are key to further investigations of etiology and to delivering new or improved procedures for early diagnosis and screening; these matters are covered in Section 6.

Introduction

(14)

World Cancer Report xiii

What information is provided in World Cancer Report?

World Cancer Report is designed to provide cancer researchers, health-care professionals, regulators, and pol- icy-makers with current findings about the causes of cancer, its prevention, and other matters tending to reduce the burden of cancer. In particular, this volume provides insights into fields of investigation that may be adjacent to those with which a particular reader may be familiar. Broader professional engagement with cancer control and a need for information by journalists, governments, and community-based cancer-oriented authorities and the teaching profession is also recognized.

As cancer research scientists, we, the editors of this World Cancer Report, readily acknowledge the need to provide information about cancer causes and prevention to the wider community with as few barriers as are compat- ible with an accurate understanding. In the past, such a commitment to immediate comprehension has involved providing explanations for technical terms and/or including a glossary. We have not adopted such options, for several reasons: to avoid interrupting the flow of information, because most of the text is immediately accessible, and considering that search engines are available to provide access to specifics.

In providing insight to those who are not necessarily undertaking research in a particular field, some background information must be specified. This is an important but secondary consideration. Indeed, this World Cancer Report is not intended to be a textbook that provides a comprehensive overview of well-established key knowledge.

Therefore, given the overall constraints on length, the authors of each chapter have provided a separate set of state- ments covering the Fundamentals (presented in a shaded sidebar). The information provided in the Fundamentals is axiomatic to the field of research covered in the chapter, but, unlike the points given in the chapter’s Summary, is not necessarily addressed in the main text of the chapter.

To meet the immediate needs of professionals for contemporary data, the authors of each chapter were asked to focus on research results achieved during the past 5 years. This determinant of content is not the same as summarizing current knowledge. For example, the chapters in Section 2, on the causes of cancer, are not necessarily comprehensive. Tobacco smoking continues to be the major preventable cause of death from cancer, and indeed from multiple other diseases, but this long-held knowledge does not, in our view, require reiteration at the expense of describing the latest research findings, including the latest approaches to smoking cessation.

A feature of this volume, as in all previous World Cancer Reports, is that the largest single section (Section 5) is that devoted to particular cancer types: 20 chapters. In numerical terms, 20 is small compared with the hundreds of tumour types as documented in the WHO Classification of Tumours series (also known as the WHO Blue Books; http://whobluebooks.iarc.fr). However, the 20 types of cancer that are covered here, when taken together, account for the overwhelming majority of cancer cases worldwide and, of greater importance, account for almost all initiatives aimed at cancer prevention.

(15)

The volumes of Cancer Incidence in Five Continents (http://ci5.iarc.fr/) and the associated GLOBOCAN database document data on incidence, prevalence, mortality, and trends for multiple cancer types across hundreds of communities. These findings are summarized and made readily accessible online through the IARC Global Cancer Observatory (https://gco.iarc.fr). Therefore, the epidemiological information in chapters in Section 5 is not documented systematically. Rather, authors were invited to give priority to recent epidemiological findings that have contributed to an increased understanding of etiology or, in some rare cases, prevention. As a result, there are marked differences between the chapters with respect to the amount of epidemiological data presented.

Similarly, information about exogenous causes or population-based screening varies markedly between cancer types, from comprehensive data to nothing relevant, and such circumstances account in large part for differences between chapters in Section 5.

Where to from here?

All the research described in this World Cancer Report is calculated, directly or indirectly, to reduce the burden of cancer, whether globally or in particular communities or for certain categories of people at risk. Typically, such outcomes occur as a result of the adoption of certain policies, either by governments or by other competent authorities. Then, many cancer-preventive options depend on individual decision-making and commitment. All such matters are themselves amenable to research.

There is no generally operative procedure that determines the transition from cancer research findings to cancer prevention policies. When such a pathway is charted for a particular innovation, the ease of its implementation will be determined by many factors as they operate in particular countries or communities. In this context, World Cancer Report is not designed as a vehicle for advocacy: research needs are not listed as such, nor are priorities specified.

The key role of cancer research in cancer prevention, as a record of achievement, is clear and unequivocal on a global scale. Since the publication of World Cancer Report 2014, the burden of cancer attributable to obesity and – separately – to pollution has been made clearer than ever before. More immediately in terms of the ultimate goal of prevention, there is global progress in reducing tobacco-attributable cancers, at least in some countries.

And where once there was the goal of increased screening for cervical cancer, there is now, through vaccination, the prospect of eliminating cervical cancer as a public health concern.

In short, “cancer research for cancer prevention” is not simply a way to describe a particular field of investigation.

Far more importantly, these words identify a pathway that may materially reduce the acknowledged burden of cancer faced by humanity. There is, in fact, no other way.

Christopher P. Wild, Elisabete Weiderpass, and Bernard W. Stewart (Editors)

(16)

As far as we know, cancer has always afflicted humans, although for centuries its relative im- pact was overshadowed by early death from infectious diseases. Until recently, informa- tion on the global distribution of cancer was limited for certain communities and countries.

We now have a reasonable basis for estimat- ing the global cancer burden. For several tu- mour types – colorectal, prostate, and breast cancer – high incidence rates were once re- stricted to North America, western Europe, and Australia, but now incidence rates are ris- ing in many other countries. Lung cancer, for which high incidence was initially restricted

to high-income countries, has long been rec- ognized as a global scourge. Previously, low- income countries primarily had a relatively high incidence of stomach, liver, and cervical cancer, but changes in incidence over time for these and other cancer types illustrate variation between countries. Finally, there are marked differences between countries or re- gions in cancer mortality, with an increasing burden in low- and middle-income countries, attributable both to less-than-optimal imple- mentation of preventive measures and to di- agnosis at a later stage, rather than an early stage, of cancer development.

The global

cancer burden

1

(17)

SUMMARY

● Cancer is the first or second leading cause of premature death (i.e. at ages 30–69 years) in 134 of 183 countries, and it ranks third or fourth in an additional 45 countries.

● Of the 15.2 million premature deaths from noncommunicable diseases worldwide in 2016, 4.5 million (29.8%) were due to cancer.

● The United Nations, within the Sustainable Development Goals agenda, has set a target to reduce the total premature mortality from noncommunicable diseases by one third by 2030.

● Mortality rates from noncommunicable diseases, and cancer in particular, are declining in most higher-income countries, but such progress is lack- ing in lower-income countries, posing challenges in meeting the Sustainable Development Goals target.

● Attaining the goal of a reduction by one third in premature mortality from the four major types of noncommunicable diseases would increase the average expected years lived in the target age group (30–69 years) by 0.64 years worldwide, with larger gains foreseen in countries with low

or medium levels of the Human Development Index (HDI).

● Feasible, affordable, and cost- effective interventions that reduce exposure to the key causes and other risk factors for cancer and for other noncommunicable diseases, increase access to essential health-care services, and ensure the availability of effective and affordable essential medicines and vaccines are crucial for disease control globally.

This chapter reviews the burden and trends of premature mortality (i.e. deaths at ages 30–69 years) from noncommunicable diseases (NCDs), with a focus on cancer, based on the WHO Global Health Estimates that are available nationally by cause and year of death [1].

When studying cancer patterns and trends, it is important to consid- er what constitutes human development, and how it may be measured.

The Human Development Index (HDI) is a composite index of three basic dimensions of human development: a long and healthy life (based on life expectancy at birth), education (based on average and expected years of schooling), and a decent standard of living (based on gross national income per capita).

The development levels of countries can be considered according to four tiers of HDI: low, medium, high, and very high HDI.

NCDs have become the leading cause of death worldwide and pose a major threat to healthy ageing, accounting for 72% of all deaths globally in 2016 [1]. The total of 40.5 million deaths from NCDs globally in 2016 is a sharp increase from the corresponding figure of 31.6 million deaths in 2000.

In 2016, about one third (15.2 million) of all deaths from NCDs oc- curred at ages 30–69 years. Of these premature deaths, 6.2 million (40.8%) were due to cardiovascular diseases, 4.5 million (29.8%) to cancer, 1.1 million (7.0%) to chronic respiratory diseases, and 0.7 million (4.5%) to diabetes [1].

These increasing trends in mortality from NCDs accompany the decline in mortality from infectious diseases, but they also result from the demographic and epidemiological transitions that are taking place.

Demographic transition refers to population-level shifts from a pattern of high birth (fertility) rates and high death (mortality) rates to one of low birth rates and low death rates. This shift increases the number of older adults, who are more susceptible to ageing-related diseases, including cancer, particularly in countries in transition [2].

Epidemiological transition re- fers to changes in mortality rates and causes of death that reflect underlying changes in exposure to risk factors. During the past century, a pattern of dominance of infectious diseases has gradually been

1.1 The burden and prevention of premature deaths from noncommunicable diseases, including cancer: a global perspective

Bernard W. Stewart (reviewer) Elisabete Weiderpass (reviewer) Christopher P. Wild (reviewer) Bochen Cao

Isabelle Soerjomataram Freddie Bray

(18)

Chapter 1.1 • The burden and prevention of premature deaths from noncommunicable diseases, including cancer: a global perspective 17

SECTION 1 CHAPTER 1.1 replaced with one in which chronic

or degenerative diseases, such as NCDs, predominate. Within this diverse group of NCDs, the relative contribution to overall deaths has evolved with trends in mortality rates. For example, there have been greater reductions in mortality rates for cardiovascular diseases than in those for cancer in many populations with medium or high HDI, and the absolute and relative reductions in cancer mortality rates have been considerably larger in populations with very high HDI (Fig. 1.1.1) [3,4].

Cancer as a leading cause of death worldwide

In the past 60 years, better sanita- tion and the development of vaccines and antibiotics have brought about dramatic declines in mortality from infectious diseases. With improving primary and secondary prevention for cardiovascular diseases, changing demographic and risk factors have led to today’s ob- servation that cancer is the first or second leading cause of premature death (i.e. at ages 30–69 years) in 134 of 183 countries, and it ranks third or fourth in an addi-

tional 45 countries (Fig. 1.1.2) [1].

Specifically, cancer is currently the leading cause of premature death in most of the countries with high or very high HDI, including Canada and the USA in North America, Argentina and Chile in South America, most countries in Europe (including France, Germany, and the United Kingdom), Australia and New Zealand in Oceania, and Japan, the Republic of Korea, and Singapore in Asia. Cancer also ranks first in Thailand and Viet Nam. Cancer is the second leading cause of premature death, after cardiovascular diseases, in Brazil, China, and many countries in eastern Europe (including the Russian Federation and Ukraine), as well as Algeria and Egypt. In most countries in sub-Saharan Africa, cancer ranks third or fourth, and there are only a few countries in this region in which cancer ranks fifth or sixth [1].

Cancer is a complex disease, for which the patterns and trends in mortality vary markedly between countries and across specific cancer types. These variations are due to differences in changing lifestyles and in local exposures to known or putative determinants, as well as an altering built environment (e.g. syn-

thetic changes to the physical environment, including structural condi- tions that have impacts on mobility and recreation, diet, and exposure to environmental pollutants). The inherent disparities and widening gaps between and within countries in levels of medical practice and health infrastructure also influence the diverging patterns and trends in cancer mortality [5–10].

In most countries with high HDI, cancer mortality rates are declining, primarily as a result of recent suc- cesses in combating common cancer types through effective interventions for prevention, early detection, and treatment. In contrast, in countries in transition, mortality rates are still increasing, or at best stabilizing, for many cancer types, including breast cancer, prostate cancer, and colorectal cancer [5,9,10].

The Sustainable De vel op - ment Goals target for combating noncommuni- cable diseases

In response to the major threat that NCDs pose to sustainable human development, and to curb the rapid rise in NCDs worldwide, the United Nations, within the Sustainable De- vel op ment Goals agenda, has set an overarching target (Target 3.4) to reduce the total premature mortality from NCDs by one third by 2030 [11,12]. For the successful realization of Target 3.4, a set of health targets have been proposed to reduce the exposure to risk factors for NCDs and to improve the prevention and treatment of NCDs.

A subsequent reduction in premature deaths from NCDs would have a profound effect on population longevity and an economic impact (see Chapter 6.9).

If the goal of a reduction by one third in premature mortality from the four major types of NCDs is attained in 2015–2030, the average expected years lived in the target age group (30–69 years) could potentially increase by 0.64 years worldwide [13].

This figure ranges from 0.44 years in countries with very high HDI to about Fig. 1.1.1. Changes between 1981–1985 and 2006–2010 in age-standardized mortal-

ity rates per 100 000 people, for ages 40–84 years in men and women combined, in populations with very high Human Development Index (HDI) and medium or high HDI.

(19)

0.70 years in countries with low or medium HDI (Fig. 1.1.3). Extending the one third reduction in premature mortality to all NCDs would lead to a further gain of 20% in average expected years lived [13]. These are significant gains when considered in light of the increases in life expectancy over the last three decades

of the 20th century: 2.5–3.7 years in countries with very high HDI and 1.1–1.4 years in countries with medium or high HDI.

Although attaining Target 3.4 of the Sustainable Development Goals is a promising prospect for population longevity in the long run, it is debatable whether countries will in-

deed meet this target. Using the his- torical trends in premature mortality from the four major types of NCDs in the 15-year period between 2000 and 2015 as a reference, one ob- serves that higher-income countries are well on track to meeting the target between 2015 and 2030, whereas lower-income countries

Data source: GHE 2016 Map production: CSU World Health Organization

on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted and dashed lines on maps represent approximate border lines for which there may not yet be full agreement.

No data Not applicable

Fig. 1.1.2. Global map of cancer as a leading cause of premature death (i.e. at ages 30–69 years), indicating the rankings, with the numbers of countries in parentheses.

No data Not applicable

Fig. 1.1.3. Global map of estimated gains in average expected years lived (LE) between ages 30 years and 69 years if the Sus tain- able Development Goals target of a reduction by one third in premature mortality from the four major types of noncommunicable dis eas es is attained in 2015–2030.

(20)

SECTION 1 CHAPTER 1.1 still face considerable challenges.

A similar picture is seen for cancer. In higher-income countries, a large part of the targeted reduction has generally been attained.

In contrast, in low- and middle-income countries the achievements are more limited (Fig. 1.1.4) [13].

It should be noted that the lack of progress in lower-income countries in 2000–2015 does not necessarily predict future failings in attaining the target in such populations in the longer term, given that many NCDs can still be successfully prevented, treated, and managed.

The distinct patterns of causes of death help to prioritize approaches to reduce mortality from specific major causes in a given country.

Specifically, cancer has surpassed cardiovascular diseases as the leading cause of death in countries with high or very high HDI. In contrast, cardiovascular diseases remain the leading cause of death in lower-income countries, largely because of inadequate and ineffective implementation of the available prevention and treatment modalities

for cardiovascular diseases. There is a clear need to prioritize prevention strategies at the national level and to structure health systems accordingly to manage the imminent epidemic of NCDs worldwide.

A key and effective measure in the prevention of cancer and other NCDs is to reduce the exposure to modifiable causes of NCDs, including several risk factors that contribute significantly to the occurrence of these diseases, such as behavioural factors (e.g. tobacco use [see Chapter 2.1], harmful alcohol consumption [see Chapter 2.3], unhealthy diet, and physical inactivity [see Chapter 2.7]), metabolic factors (e.g. high blood pressure, overweight and obesity, and high cholesterol level), and environmental factors (e.g. air pollution [see Chapter 2.9]), [12,14]. In many middle-income countries, risk factors for NCDs continue to prevail.

For example, the highest levels of smoking prevalence, harmful alcohol consumption, and high blood pressure globally are observed in countries of the former Soviet Union

and other countries in central and eastern Europe [12,15–17], leading to high rates of premature mortality from NCDs, including cancer.

However, lower-income countries face the additional burden of poverty-related NCDs, such as infection-related cancers (including stomach cancer [see Chapter 5.4], liver cancer [see Chapter 5.6], and cervical cancer [see Chapter 5.10]), cardiovascular diseases due to fetal and childhood malnutrition, and respiratory diseases that are correlated with a poor living environment [18,19].

As countries progress societally and economically, and epidemiological transitions continue, the reduction in NCDs linked to poverty-related factors is expected to be offset by increasing exposure to many behavioural, environmental, and occupa- tional risk factors linked with indus- trialized settings, including tobacco use, harmful alcohol consumption, and physical inactivity [20–26]. The path towards attaining Target 3.4 of the Sustainable Development Goals will be particularly challenging for resource-constrained countries if

Low / Medium HDI

0 4 8 12 14

10

6

Change in Risk of dying (%),30-69 years old 2

5.5

India

-1% 5.7

Morocco -3%

7.6 6.4

Philippines -16%

9.2 7.6

South Africa -17%

13.9

11

Uganda -21%

High / Very High HDI

0 4 8 12

7.1 5.5

Sweden -23%

7.9 6.7

Brazil -16%

8.7

6.8

USA -21%

9.3

7.2

China -23%

13

11

Russian Federation

-16%

Reducing the risk in 2000 by 1/3

2000 2015

14

10

6

2 Change in Risk of dying (%),30-69 years old Fig. 1.1.4. Changes between 2000 and 2015 in the risk of dying from cancer at ages 30–69 years, for selected countries with low or medium Human Development Index (HDI) and high or very high HDI.

(21)

their adoption of unhealthy lifestyles and activities with high environmental impact is not halted. Therefore, in the coming decades it will be increas- ingly critical to mitigate the rise in NCDs in lower-income countries by preventing the adoption of unhealthy behaviours (see Chapter 6.1) and ensuring that environmental actions are sustainable [27,28].

To curb the rising burden of NCDs, WHO proposed a “best buys” package to facilitate interventions that are feasible, affordable, and cost-effective [12,29]. An extended list of options to reduce the prevalence of tobacco smoking, harmful alcohol consumption, unhealthy diet, and physical inactivity as well as environmental action, for example to reduce air pollution, are essential elements to control NCDs, including cancer.

Furthermore, measures proposed by the WHO “best buys” and by the

“essential package” of interventions presented in the third edition of Disease Control Priorities – includ- ing implementing vaccination programmes, extending the preventive and early detection measures for cancer at the primary care level, and improving access to services for cancer and other NCDs – are

expected to contribute substantially to a reduction in premature deaths from NCDs by 2030 [30,31]. Finally, establishing high-quality surveillance systems for cancer and other NCDs is imperative to plan and evaluate national responses to the Sustainable Development Goals target [29].

The slow pace of progress in resource-limited countries that are undergoing major transitions, relative

to the pace in higher-resource countries (Fig. 1.1.4) highlights the need for accelerated actions to achieve the Sustainable Development Goals target in these countries. However, inadequate access to affordable primary care, early detection, and treatment continues to be a bar- rier to effective prevention and treatment in these settings, leading to poorer survival outcomes in patients [12,17]. For example, whereas cancer surgery services are available in 95% of high-income countries, the equivalent rate is only about 25%

in low-income countries [32], leading to substantially higher cancer case fatality in lower-income countries (70%) than in higher-income countries (45%) [33]. As part of the Sustainable Development Goals targets, achieving universal health coverage, including access to essential health-care services and access to effective and affordable essential medicines and vaccines for NCDs for all, is crucial to ensure a narrow- ing of the inequity gap and a reduction in mortality from NCDs globally.

The potential for health improve- ment is particularly striking in low- and middle-income countries, if the prompt adoption of “best buys” interventions leads to the Sustainable Development Goals target being met, because in these countries Fig. 1.1.5. Dancers in Ayquina, Chile, illustrate the diversity of communities affected

by cancer. In Chile, the incidence rates of cancer of the gall bladder are among the highest in the world.

Fig. 1.1.6. The disparities that are evident within many countries are illustrated in this view of Manila, Philippines.

(22)

SECTION 1 CHAPTER 1.1 NCDs commonly rank higher as a

cause of death. A parallel impact across the four major types of NCDs is expected, with a marked reduction in cancer mortality rates, many of which have stagnated nationally.

In addition to improved health out-

comes, the additional societal and economic potential of these interventions for NCDs is large, because the targeted decline in mortality would bring about a substantial increase in the number of person-years lived in the most productive age groups,

hence increasing workplace produc- tivity and reducing costs of health care and social care. Ultimately, these potential benefits provide further arguments for implementing actions aimed at reducing the global burden of NCDs.

References

1. WHO (2018). Global health estimates 2016:

deaths by cause, age, sex, by country and by region, 2000–2016. Geneva, Switzerland:

World Health Organization. Available from:

https://www.who.int/healthinfo/global_

burden_disease/en/.

2. Caldwell JC (1976). Toward a restate- ment of demographic transition theory.

Popul Dev Rev. 2(3/4):321–66. https://doi.

org/10.2307/1971615

3. Kanavos P (2006). The rising burden of cancer in the developing world.

Ann Oncol. 17(Suppl 8):viii15–viii23.

https://doi.org/10.1093/annonc/mdl983 PMID:16801335

4. Omran AR (1971). The epidemiologic transition. A theory of the epidemiology of population change. Milbank Mem Fund Q. 49(4):509–38. https://doi.

org/10.2307/3349375 PMID:5155251 5. DeSantis CE, Bray F, Ferlay J, Lortet-

Tieulent J, Anderson BO, Jemal A (2015).

International variation in female breast cancer incidence and mortality rates. Cancer Epidemiol Biomarkers Prev. 24(10):1495–

506. https://doi.org/10.1158/1055-9965.

EPI-15-0535 PMID:26359465

6. Torre LA, Bray F, Siegel RL, Ferlay J, Lortet-Tieulent J, Jemal A (2015). Global cancer statistics, 2012. CA Cancer J Clin.

65(2):87–108. https://doi.org/10.3322/caac.

21262 PMID:25651787

7. Torre LA, Siegel RL, Ward EM, Jemal A (2014). International variation in lung cancer mortality rates and trends among women. Cancer Epidemiol Biomarkers Prev. 23(6):1025–36. https://doi.org/10.1158/

1055-9965.EPI-13-1220 PMID:24836468 8. Ferro A, Peleteiro B, Malvezzi M, Bosetti

C, Bertuccio P, Levi F, et al. (2014).

Worldwide trends in gastric cancer mortality (1980-2011), with predictions to 2015, and incidence by subtype. Eur J Cancer.

50(7):1330–44. https://doi.org/10.1016/j.

ejca.2014.01.029 PMID:24650579

9. Siegel R, Desantis C, Jemal A (2014).

Colorectal cancer statistics, 2014. CA Cancer J Clin. 64(2):104–17. https://doi.

org/10.3322/caac.21220 PMID:24639052 10. Center MM, Jemal A, Lortet-Tieulent J,

Ward E, Ferlay J, Brawley O, et al. (2012).

International variation in prostate cancer incidence and mortality rates. Eur Urol.

61(6):1079–92. https://doi.org/10.1016/j.

eururo.2012.02.054 PMID:22424666 11. United Nations General Assembly (2015).

Transforming our world: the 2030 Agenda for Sustainable Development. Available from: https://sustainabledevelopment.un.

org/post2015/transformingourworld.

12. WHO (2014). Global status report on noncommunicable diseases 2014. Geneva, Switzerland: World Health Organization.

Available from: https://apps.who.int/iris/

handle/10665/148114.

13. Cao B, Bray F, Ilbawi A, Soerjomataram I (2018). Effect on longevity of one-third reduction in premature mortality from non-communicable diseases by 2030:

a global analysis of the Sustainable Development Goal health target. Lancet Glob Health. 6(12):e1288–e1296. https://

doi.org/10.1016/S2214-109X(18)30411-X PMID:30420032

14. GBD 2015 Risk Factors Collaborators (2016). Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupation- al, and metabolic risks or clusters of risks, 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015.

Lancet. 388(10053):1659–724. https://

doi.org/10.1016/S0140-6736(16)31679-8 PMID:27733284

15. Ezzati M, Lopez AD, Rodgers A, Vander Hoorn S, Murray CJ; Comparative Risk Assessment Collaborating Group (2002). Selected major risk factors and global and regional burden of disease.

Lancet. 360(9343):1347–60. https://doi.

org/10.1016/S0140- 6736(02)11403- 6 PMID:12423980

16. Danaei G, Finucane MM, Lin JK, Singh GM, Paciorek CJ, Cowan MJ, et al.;

Global Burden of Metabolic Risk Factors of Chronic Diseases Collaborating Group (Blood Pressure) (2011). National, regional, and global trends in systolic blood pressure since 1980: systematic analysis of health examination surveys and epidemiological studies with 786 country-years and 5.4 million partici- pants. Lancet. 377(9765):568–77. https://

doi.org/10.1016/S0140-6736(10)62036-3 PMID:21295844

17. Di Cesare M, Khang Y-H, Asaria P, Blakely T, Cowan MJ, Farzadfar F, et al.; Lancet NCD Action Group (2013). Inequalities in non-communicable diseases and effective responses. Lancet. 381(9866):585–

97. https://doi.org/10.1016/S0140-6736 (12)61851-0 PMID:23410608

18. Ezzati M, Riboli E (2012). Can noncommunicable diseases be prevented?

Lessons from studies of populations and individuals. Science. 337(6101):1482–7.

https://doi.org/10.1126/science.1227001 PMID:22997325

19. de Martel C, Ferlay J, Franceschi S, Vignat J, Bray F, Forman D, et al. (2012). Global burden of cancers attributable to infec- tions in 2008: a review and synthetic analysis. Lancet Oncol. 13(6):607–15. https://

doi.org/10.1016/S1470-2045(12)70137-7 PMID:22575588

20. WHO (2017). WHO report on the global tobacco epidemic, 2017: monitoring tobacco use and prevention policies. Geneva, Switzerland: World Health Organization.

handle/10665/255874.

21. Singh T, Arrazola RA, Corey CG, Husten CG, Neff LJ, Homa DM, et al. (2016).

Tobacco use among middle and high school students – United States, 2011–

2015. MMWR Morb Mortal Wkly Rep.

65(14):361–7. https://doi.org/10.15585/

mmwr.mm6514a1 PMID:27077789

(23)

22. Samet JM, Yoon S-Y, editors (2001).

Women and the tobacco epidemic: challenges for the 21st century. Geneva, Switzerland: World Health Organization.

handle/10665/66799.

23. Guthold R, Louazani SA, Riley LM, Cowan MJ, Bovet P, Damasceno A, et al. (2011).

Physical activity in 22 African countries:

results from the World Health Organization STEPwise approach to chronic disease risk factor surveillance. Am J Prev Med.

41(1):52–60. https://doi.org/10.1016/j.

amepre.2011.03.008 PMID:21665063 24. Pratt M, Sarmiento OL, Montes F, Ogilvie

D, Marcus BH, Perez LG, et al.; Lancet Physical Activity Series Working Group (2012). The implications of megatrends in information and communication tech- nology and transportation for changes in global physical activity. Lancet. 380 (9838):282–93. https://doi.org/10.1016/

S0140-6736(12)60736-3 PMID:22818940 25. Bauman AE, Reis RS, Sallis JF, Wells JC,

Loos RJF, Martin BW; Lancet Physical Activity Series Working Group (2012).

Correlates of physical activity: why are some people physically active and others not? Lancet. 380(9838):258–71. https://

doi.org/10.1016/S0140-6736(12)60735-1 PMID:22818938

26. WHO (2014). Global status report on alcohol and health – 2014. Geneva, Switzerland: World Health Organization.

handle/10665/112736.

27. Preston SH (1976). Mortality patterns in national populations: with special reference to recorded causes of death. New York (NY), USA: Academic Press.

28. Salomon JA, Murray CJL (2002). The epidemiologic transition revisited: composi- tional models for causes of death by age and sex. Popul Dev Rev. 28(2):205–28. https://

doi.org/10.1111/j.1728-4457.2002.00205.x 29. WHO (2013). Global action plan for the

prevention and control of noncommunicable diseases 2013–2020. Geneva, Switzerland: World Health Organization.

handle/10665/94384.

30. Gelband H, Jha P, Sankaranarayanan R, Horton S, editors (2015). Disease control priorities. 3rd ed. Vol. 3, Cancer.

Washington (DC), USA: World Bank.

31. Gelband H, Sankarayanarayanan S, Gauvreau CL, Horton S, Anderson BO, Bray F, et al.; Disease Control Priorities-3 Cancer Author Group (2016). Costs, affordability, and feasibility of an essential package of cancer control interventions in low-income and middle- income countries: key messages from Disease Control Priorities, 3rd edition.

Lancet. 387(10033):2133–44. https://

doi.org/10.1016/S0140-6736(15)00755-2 PMID:26578033

32. WHO (2016). Assessing national ca- pacity for the prevention and control of noncommunicable diseases: report of the 2015 global survey. Geneva, Switzerland: World Health Organization.

handle/10665/246223.

33. Ferlay J, Ervik M, Lam F, Colombet M, Mery L, Piñeros M, et al. (2018). Global Cancer Observatory: Cancer Today. Lyon, France: International Agency for Research on Cancer. Available from: https://gco.iarc.

fr/today.

(24)

23

SECTION 1 CHAPTER 1.2

SUMMARY

● In men, lung cancer incidence and mortality rates vary across countries and are almost invari- ably correlated with the prevalence of tobacco smoking 20–

30 years earlier. In women, the smoking epidemic typically be- gan later, or – in some countries – not at all, and this is reflected in the corresponding rates.

● Rising breast cancer incidence rates are correlated with trends towards earlier ages at menar- che, later ages at first birth, and lower parity. In many countries with high levels of the Human Development Index (HDI), incidence rates have stabilized and mortality rates are declining, whereas in countries in transition towards higher HDI levels, mortality trends have tended to parallel the increasing incidence trends.

● Incidence rates of colorectal cancer have increased in countries in transition, whereas in countries with high HDI, rates have either stabilized or decreased.

However, incidence is increasing in younger age groups and in recent generations in a diverse set of countries. Mortality rates have decreased in countries with high HDI; mortality rates are increasing in many low- and middle-income countries.

● An increase in prostate cancer incidence rates followed by a decline, as observed in the USA, is attributable to prostate- specific antigen (PSA) testing.

In several countries in Asia and Latin America, incidence rates increased substantially and then stabilized. Mortality rates have been declining in most countries.

● Worldwide, stomach cancer ranks fifth in terms of incidence and third in terms of mortality.

Incidence and mortality rates of stomach cancer (predomi- nantly the non-cardia type) are decreasing, whereas incidence of cancer of the cardia region of the stomach is increasing in several populations. Most cases of stomach cancer are attributable to infection with Helicobacter pylori.

● Cervical cancer incidence and mortality rates have declined in most countries in recent decades, as a result of the detection of precancerous lesions by screening, but increasing rates have been observed in younger generations of women in some countries. Global elimination of the disease – in terms of cervical cancer no longer being considered a public health problem – is attainable during this century through HPV vaccination and screening programmes.

This chapter reviews the incidence and mortality trends for the six most common cancer types worldwide (lung cancer, breast cancer, colorectal cancer, prostate cancer, stomach cancer, and cervical cancer) and the main determinants of these trends, including the role of the changing prevalence and distribution of key risk factors as well as the impact of preventive, screening, and therapeutic interventions.

IARC is responsible for the com- pilation, estimation, and reporting of cancer statistics generated through flagship projects and databases, including Cancer Incidence in Five Continents (http://ci5.iarc.fr) and GLOBOCAN, for which the resulting statistics are disseminated on the Global Cancer Observatory, an inter- active, user-friendly, and data-driven online interface (http://gco.iarc.fr).

The primary source for this chapter is the cancer incidence trends from successive volumes of Cancer Incidence in Five Continents, the compendium of data sets from national or subnational high-quality population-based cancer registries.

Equivalent data on cancer mortality trends were obtained from the national statistics compiled in the WHO Mortality Database (https://www.who.

int/healthinfo/mortality_data/en/).

This chapter also makes reference to the current global burden of the six most common cancer types using the GLOBOCAN 2018 estimates of incidence and mortality, which are provided for 185 countries

1.2 Global trends in cancer incidence and mortality

Bernard W. Stewart (reviewer) Elisabete Weiderpass (reviewer) Christopher P. Wild (reviewer) Isabelle Soerjomataram

Freddie Bray

World Cancer Report

Cancer research for cancer prevention

World Cancer

Report

World Cancer Report

Cancer research

for cancer prevention

World Cancer Report

Cancer research for cancer prevention

Contributors

Contents

Foreword

Preface

The scope of this World Cancer Report

Introduction

What information is provided in World Cancer Report?

Where to from here?

As far as we know, cancer has always afflicted humans, although for centuries its relative im- pact was overshadowed by early death from infectious diseases. Until recently, informa- tion on the global distribution of cancer was limited for certain communities and countries.

The global

cancer burden

1

SUMMARY

1.1 The burden and prevention of premature deaths from noncommunicable diseases, including cancer: a global perspective

Cancer as a leading cause of death worldwide

The Sustainable De vel op - ment Goals target for combating noncommuni- cable diseases

References

SUMMARY

1.2 Global trends in cancer incidence and mortality