WHO Cancer Report
This report from the World Health Organization (WHO) is based on research studies
on cancer around the world can be found at
www.who.int Please do not become one of their predicted statistic.
Global cancer rates could increase by 50% to 15 million by 2020
World Cancer Report provides clear evidence that action on smoking, diet and
infections can prevent one third of cancers, another third can be cured
3 April 2003 | GENEVA -- Cancer rates could further increase by 50% to 15
million new cases in the year 2020, according to the World Cancer Report, the
most comprehensive global examination of the disease to date. However, the
report also provides clear evidence that healthy lifestyles and public health
action by governments and health practitioners could stem this trend, and
prevent as many as one third of cancers worldwide.
In the year 2000, malignant tumours were responsible for 12 per cent of the
nearly 56 million deaths worldwide from all causes. In many countries, more than
a quarter of deaths are attributable to cancer. In 2000, 5.3 million men and 4.7
million women developed a malignant tumour and altogether 6.2 million died from
the disease. The report also reveals that cancer has emerged as a major public
health problem in developing countries, matching its effect in industrialized
nations.
“The World Cancer Report tells us that cancer rates are set to increase at an
alarming rate globally. We can make a difference by taking action today. We have
the opportunity to stem this increase. This report calls on Governments, health
practitioners and the general public to take urgent action. Action now can
prevent one third of cancers, cure another third, and provide good, palliative
care to the remaining third who need it, "said Dr. Paul Kleihues, Director of
the International Agency for Research on Cancer (IARC) and co-editor of the
World Cancer Report.
The World Cancer Report is a concise manual describing the global burden, the
causes of cancer, major types of malignancies, early detection and treatment.
The 351-page global report is issued by IARC, which is part of the World Health
Organization (WHO).
Dr Gro Harlem Brundtland, Director-General of WHO, states: “The report
provides a basis for public health action and assists us in our goal to reduce
the morbidity and mortality from cancer, and to improve the quality of life of
cancer patients and their families, everywhere in the world,”
Examples of areas where action can make a difference to stemming the increase
of cancer rates and preventing a third of cases are:
- Reduction of tobacco consumption. It remains the most important avoidable
cancer risk. In the 20th century, approximately 100 million people died
world-wide from tobacco-associated diseases
- A healthy lifestyle and diet can help. Frequent consumption of fruit and
vegetables and physical activity can make a difference.
- Early detection through screening, particularly for cervical and breast
cancers, allow for prevention and successful cure.
The predicted sharp increase in new cases – from 10 million new cases
globally in 2000, to 15 million in 2020 - will mainly be due to steadily ageing
populations in both developed and developing countries and also to current
trends in smoking prevalence and the growing adoption of unhealthy lifestyles.
“Governments, physicians, and health educators at all levels could do much
more to help people change their behaviour to avoid preventable cancers,” says
Bernard W. Stewart, Ph.D., co-editor of the report, Director of Cancer Services,
and Professor, Faculty of Medicine, University of New South Wales, Australia.
“If the knowledge, technology and control strategies outlined in the World
Cancer Report were applied globally, we would make major advances in preventing
and treating cancers over the next twenty years and beyond.”
From a global perspective, there is strong justification for focusing cancer
prevention activities particularly on two main cancer-causing factors - tobacco
and diet. We also need to continue efforts to curb infections which cause
cancers,” said Dr Rafael Bengoa, Director, Management of Non-communicable
disease at WHO. “These factors were responsible for 43 per cent of all cancer
deaths in 2000, that is 2.7 million fatalities, and 40 per cent of all new
cases, that is four million new cancer cases.”
As part of an effort to stem this trend, WHO is engaged in efforts to stem
both tobacco use, and to improve diet, nutrition and physical activity. Tobacco
consumption remains the most important avoidable cancer risk. The report reviews
and recommends a number of strategies to reduce global tobacco consumption,
requiring the coordinated involvement of government and community health
organizations, health care professionals and individuals. The groundbreaking
public health treaty - the Framework Convention on Tobacco Control - which the
Member States of WHO have agreed to submit to the World Health Assembly in May
2003, represents a powerful tool to ensure that such strategies are implemented.
WHO is also engaged in preparing a Global Strategy on Diet, Physical Activity
and Health, under a May 2002 mandate from Member States to address the growing
global burden of chronic diseases, including cancers, cardiovascular diseases,
diabetes and obesity. WHO is consulting widely with Member States, other UN
agencies, the private sector and civil society on the strategy, which will be
presented to the World Health Assembly in May 2004. The strategy will contain
recommendations for governments on nutrition and physical activity goals and
population-based interventions to reduce the prevalence of chronic disease
including cancer.
The World Cancer Report – The major findings
Tobacco, the case for primary prevention
Tobacco consumption remains the most important avoidable cancer risk. In the
20th century, approximately 100 million people died world-wide from
tobacco-associated diseases (cancer, chronic lung disease, cardiovascular
disease and stroke). Half of regular smokers are killed by the habit. One
quarter of smokers will die prematurely during middle age (35 to 69 years).
The lung cancer risk for regular smokers as compared to non-smokers (relative
risk, RR) is between 20 and 30 fold. In countries with a high smoking prevalence
and where many women have smoked cigarettes throughout adult life, roughly 90
per cent of lung cancers in both men and women are attributable to cigarette
smoking. For bladder and renal pelvis, the RR is five-six but this means that
more than 50 per cent of cases are caused by smoking.
The RR for cancers of the oral cavity, oral cavity, pharynx, larynx and
squamous cell carcinoma of the oesophagus is greater than six, and three-four
for carcinomas of the pancreas. These risk estimates are higher than previously
estimated and unfortunately, additional cancer sites with a RR of two-three have
been identified as being associated with tobacco smoking, including cancers of
the stomach, liver, uterine cervix, kidney (renal cell carcinoma) nasal cavities
and sinuses, esophagus (adenocarcinoma) and myeloid leukaemia.
Involuntary (passive) tobacco smoke is carcinogenic and may increase the lung
cancer risk by 20 per cent. There is currently no evidence that smoking causes
breast, prostate or endometrial cancer of the uterus.
The deadly smoking habit is particularly worrying in Central and Eastern
Europe and many developing and newly industrialized countries. The tendency of
youth around the world to start smoking at younger and younger ages will
predispose them to substantial risks in later life.
While it is best never to start smoking, epidemiological evidence supports
the enormous benefits of cessation. The greatest reduction in the number of
cancer deaths within the next several decades will be due to those who stop the
habit. The greatest effect results from stopping smoking in the early 30s, but a
very impressive risk reduction of more than 60per cent is obtained even when the
habit is quit after the age of 50 years.
The report reviews and recommends a number of strategies to reduce global
tobacco consumption, requiring the coordinated involvement of government and
community health organizations, health care professionals and individuals. The
groundbreaking public health treaty - the Framework Convention on Tobacco
Control represents a powerful tool to ensure that such strategies are
implemented.
Infection and cancer: intervention is key
In developing countries, up to 23 per cent of malignancies are caused by
infectious agents, including hepatitis B and C virus (liver cancer), human
papillomaviruses (cervical and ano-genital cancers), and Helicobacter pylori
(stomach cancer). In developed countries, cancers caused by chronic infections
only amount to approximately 8 per cent of all malignancies. This discrepancy is
particularly evident for cervical cancer. In developed countries with an
excellent public health infrastructure and a high compliance of women, early
cytological detection of cervical cancer (PAP smear) has led to an impressive
reduction of mortality while in other world regions, including Central America,
South East Africa and India, incidence and mortality rates are still very high.
Today, more than 80 per cent of all cervical cancer deaths occur in developing
countries.
Vaccinations could be key to preventing these cancers. HBV vaccination has
already been shown to prevent liver cancer in high-incidence countries and it is
likely that human papillomavirus (HPV) vaccination will become a reality in 3 to
5 years.
In the gastro-intestinal tract (GIT), any chronic tissue damage with necrosis
and regeneration carries an in creased cancer risk, e.g. consumption of very hot
beverages (squamous cell carcinoma of the esophagus), gastro-oesophageal reflux
(adenocarcinoma of the esophagus), chronic gastritis induced by H. pylori
infection (stomach cancer), Crohn’s disease (cancer of the small intestines) and
ulcerative colitis (colon cancer).
Poverty, affluence and the global burden of cancer
In developed countries, the probability of being diagnosed with cancer is more
than twice as high as in developing countries. However, in rich countries, some
50 per cent of cancer patients die of the disease, while in developing
countries, 80 per cent of cancer victims already have late-stage incurable
tumors when they are diagnosed, pointing to the need for much better detection
programs.
The main reasons for the greater cancer burden of affluent societies are the
earlier onset of the tobacco epidemic, the earlier exposure to occupational
carcinogens, and the Western nutrition and lifestyle. However, with increasing
wealth and industrialization, many countries undergo rapid lifestyle changes
that will greatly increase their future disease burden.
“Once considered a “Western” disease, the Report highlights that more than 50
per cent of the world’s cancer burden, in terms of both numbers of cases and
deaths, already occurs in developing countries. “Cancer has emerged as a major
public health problem in developing countries for the first time, matching its
effect in industrialized nations. This is a global problem, and it’s growing.
But, we can take steps to slow this growth,” says Paul Kleihues, MD, Director of
IARC and co-editor of the World Cancer Report.
The Western lifestyle and its health risks
The Western lifestyle is characterized by a highly caloric diet, rich in fat,
refined carbohydrates and animal protein, combined with low physical activity,
resulting in an overall energy imbalance. It is associated with a multitude of
disease conditions, including obesity, diabetes, cardiovascular disease,
arterial hypertension and cancer.
Malignancies typical for affluent societies are cancers of the breast,
colon/rectum, uterus (endometrial carcinoma), gallbladder, kidney and
adenocarcinoma of the oesophagus. Prostate cancer is also strongly related to
the Western lifestyle, but there is an additional ethnic component; black people
appear to be at a greater risk than whites and the latter at higher risk than
Asian populations. Similar lifestyles are associated with a similar tumour
burden. Since they have a common cause, these neoplasms typically go together.
There is no region in the world that has a high incidence of breast cancer
without a concurrent colon cancer burden.
Obesity is spreading epidemically throughout the world. It visualizes a
chronic energy imbalance and is an independent predictor of an increased cancer
risk, particularly for carcinomas of the uterine endometrium, kidney and gall
bladder.
Together with the independent Expert Report on diet and chronic disease,
released in March 2003 by WHO and FAO (Food and Agriculture Organization) the
World Cancer Report provides policymakers with the latest information on which
to base advice.
Nutrition and cancer – the good news
Stomach cancer is among the most common malignancies worldwide, with some
870,000 cases every year, and 650,000 deaths. About 60 per cent of cases occur
in developing countries, with the highest incidence rates coming in Eastern
Asia, the Andean regions of South America and Eastern Europe. The good news is
that stomach cancer is declining world-wide, in some regions almost
dramatically. In Switzerland and neighbouring European countries, the mortality
fell by 60 per cent within one generation. If this trend continues, stomach
cancer may in some world regions become a rare disease during the next 30 years.
The main reason for this welcome development is the invention of the
refrigerator, allowing fish and meat preservation without salting. The drop in
incidence and mortality rates is therefore particularly impressive in Nordic
countries in which fish consumption is traditionally high, e.g. Iceland. In
populations that still prefer salty food, e.g. Portugal and Brazil (salted cod,
bacalao), Japan and Korea (salted pickles and salad), stomach cancer rates are
still high but have also started to decline significantly. An additional factor
contributing to this trend is the availability in many countries of fresh fruit
and vegetables throughout the year.
Cancer prevention: a healthy diet can help!
Epidemiological studies indicate that the frequent consumption of fruit and
vegetables may reduce the risk of developing cancers of epithelial origin,
including carcinomas of the pharynx, larynx, lung, oesophagus, stomach, colon
and cervix. Recent data from the European Prospective Investigation into Cancer
and Nutrition (EPIC), suggests that a daily consumption of 500 grams (1.1. lbs.)
of fruits and vegetables can decrease incidence of cancers of the digestive
tract by up to 25 per cent.
The report also says that given the multi-faceted impact of diet on cancer,
many countries should encourage consumption of locally produced vegetables,
fruit and agricultural products, and avoid the adoption of Western style dietary
habits. IARC says that such actions would have health benefits beyond cancer,
since other common non-communicable diseases, notably cardiovascular disease and
diabetes, share the same lifestyle-related risk factors.
Early detection – the best strategy second to primary prevention The best
possible prevention against cancer remains the avoidance of exposure to
cancer-causing agents: this is called primary prevention (eg tobacco, industrial
carcinogens, etc).
There is sound evidence that the recent decline in cancer mortality observed
in several countries is to a significant extent due to early detection.
Responsible for this success are not only improvements in imaging (mammography,
magnetic resonance (MR) and computed tomography (CT) imaging), but also a higher
degree of disease awareness and educational programmes on typical early
symptoms. Most successful so far has been the early detection of cervical cancer
by cytology and of breast cancer by mammography. A recent analysis by an IARC
Working Group concluded that under trial conditions, mammography screening may
reduce breast cancer mortality by 25-30 per cent and that in nation-wide
screening programmes a reduction by 20 per cent appears feasible. There is also
emerging evidence that prostate cancer screening by assessment of serum PSA
levels may result in lower mortality rates but management of early lesions is
still very invasive. For colon cancer, colonoscopy is considered the gold
standard although its application in population-based screening programmes would
require considerable medical resources.
Cancer control strategies
The aim of cancer control is a reduction in both the incidence of the disease
and the associated morbidity and mortality, as well as improved life for cancer
patients and their families. In addition to substantial opportunities for
primary prevention, the World Cancer Report also emphasizes the potential of
early detection, treatment and palliative care. It urges all countries to
establish comprehensive national cancer control programmes, aimed at reducing
the incidence of the disease and improving the quality of life for cancer
patients and their families. In developing countries in particular, where a
large proportion of cancers are detected late in the course of the disease,
efforts to achieve earlier diagnosis and delivery of adequate palliative care
and pain relief deserve urgent attention.
Cancer by the Numbers
Lung cancer is the most common cancer worldwide, accounting for 1.2 million new
cases annually; followed by cancer of the breast, just over 1 million cases;
colorectal, 940,000; stomach, 870,000; liver, 560,000; cervical, 470,000;
esophageal, 410,000; head and neck, 390,000; bladder, 330,000; malignant
non-Hodgkin lymphomas, 290,000; leukemia, 250,000; prostate and testicular,
250,000; pancreatic, 216,000; ovarian, 190,000; kidney, 190,000; endometrial,
188,000; nervous system, 175,000; melanoma, 133,000; thyroid, 123,000; pharynx,
65,000; and Hodgkin disease, 62,000 cases.
The three leading cancer killers are different than the three most common
forms, with lung cancer responsible for 17.8 per cent of all cancer deaths,
stomach, 10.4 per cent and liver, 8.8 per cent.
Industrial nations with the highest overall cancer rates include: U.S.A,
Italy, Australia, Germany, The Netherlands, Canada and France. Developing
countries with the lowest cancer were in Northern Africa Southern and Eastern
Asia. (A complete list of cancer rates by countries can be found at http://www-dep.iarc.fr/.
Lung cancer in women
Lung cancer strikes 900,000 men and 330,000 women yearly. Among men, smoking
causes more than 80 per cent of lung cancer cases. In women, smoking is the
cause of 45 per cent of all lung cancer worldwide, but more than 70 per cent in
North America and Northern Europe. In both men and women, the incidence of lung
cancer is low before age 40, and increases up to age 70 or 75.
The rise in female smoking prevalence is a major public health concern. In
the US, more women die from smoking-induced lung cancer than from breast cancer
and in some Nordic countries, including Iceland and Denmark, female lung cancer
deaths have begun to outnumber male tobacco victims. Considering that in several
European countries up to 50 per cent of young women are now regular smokers,
this will cause a disease burden that significantly reduces women’s health in
decades to come.
Colon cancer
Cancers of the colon and rectum are rare in developing countries, but are the
second most frequent malignancy in affluent societies. More than 940,000 cases
occur annually worldwide, and nearly 500,000 die from it each year.
A major cause is a diet rich in fat, refined carbohydrates and animal
protein, combined with low physical activity. Genetic susceptibility appears to
be involved in less than five per cent of cases. Epidemiological studies suggest
that risk can be reduced by decreasing meat consumption (particularly processed
meat) and increasing the intake of vegetables and fruit. Migrant populations
rapidly reach the higher level of risk of the adopted country, another sign that
environmental factors play a major role.
Colonocopy is the most reliable means for early detection. Progressively
improved diagnosis and treatment has resulted in a five-year survival rate of 50
per cent.
Key statements
- Tobacco use is the major preventable cause of cancer in the world.
- Molecular genome research will reveal a tremendous amount of information
on cancer but it is not clear how easy these discoveries will translate into
actual lives saved and may well be restricted to rare cancers.
- As developing countries succeed in achieving lifestyles similar to Europe,
North America, Australia, New Zealand and Japan, they will also encounter much
higher cancer rates, particularly cancers of the breast, colon, prostate and
uterus (endometrial carcinoma).
- Researchers will demonstrate that successful behavioral changes in
tobacco, alcohol and diet will prevent far more cancers than the elimination
of toxins such as industrial pollution, car exhaust and dioxins;
- The Pap smear for cervical cancer is the single best cancer screening
procedure. The medical community must develop a wide spectrum of tests for
other cancers and are now evaluating many procedures to determine if they are
effective and practical;
- The major differences of cancer between the sexes are the predominance in
males with lung, liver, stomach, esophageal and bladder cancer; for the most
part, these differences derive from patterns of exposure to the causes of the
cancers, to a smaller extent they reflect intrinsic gender differences in
susceptibility.
- More than one million cases of breast cancer occur worldwide annually,
with some 580,000 cases occurring in developed countries (>300/100,000
population per year) and the remainder in developing countries (usually
<1500/100,000 population per year), despite their much higher overall
population and younger age.
- In 2000, the last year for which global data exists, some 400,000 women
died from breast cancer, representing 1.6 per cent of all female deaths. The
proportion of breast cancer deaths was far higher in the rich countries (2 per
cent of all female deaths) than in economically poor regions (0.5per cent).
- “The good news is that breast cancer mortality rates have started to
decline in North America, Western Europe and Australia, mainly due to
improvements in early detection and treatment programs such as chemotherapy
and tamoxifen,” says Dr. Stewart. “Five-year survival rates are higher than 75
per cent in most developed countries.”
- The report says that the worldwide breast cancer epidemic has many
causative factors, including reproductive history, genetics, radiation
(especially at times of breast development), and the Western lifestyle with a
high caloric diet, obesity and lack of physical activity.
- “Dietary recommendation require close coordination with programs for the
prevention of other related non-communicable diseases, mainly cardiovascular
diseases, chronic obstructive pulmonary diseases and diabetes,” Dr. Kleihues
says.
IARC also calls for effective and carefully evaluated school education
programs for tobacco abstinence and healthy dietary habits, especially because
very few countries currently have effective education programs. The Lyons,
France-based IARC also calls for national cancer control programs can help to
ensure that governments take the necessary actions to guarantee that the public
has the motivation to adopt healthy personal habits.
“New drugs will not necessarily eradicate tumors, but when used in
combination with other agents, may turn many cases of rapidly fatal cancer into
‘manageable’ chronic illness,” Dr. Stewart says. Control -- For maximum impact
on the cancer problem, societies must change their priority from treatment and
detection to prevention, the IARC report says.
At the core of this cancer control strategy, the essential package includes
cost-effective interventions for the following components: tobacco control,
infection control, healthy eating, a curable cancer program and palliative care.
“By acting now, by the year 2020, countries can achieve significant
reductions in cancer rates and in mortality from cancer,” says Dr. Stewart.
“These opportunities exist, and the only question is whether we will take
advantage of them for the benefit of all humankind.”
“This is a break out book that will be distributed to government health
ministries, medical schools and general bookstores,” Dr Kleihues says. “There is
no book like this in the world. No one has attempted to do what this book has
attempted to do. We tried to produce a book that has much technical detail that
is both relevant and understandable to laymen, as to the specialists.”
For further information:
For US media enquiries please contact: Ian Larsen, Hoffman & Hoffman Public
Relations, +1 703 820 2244 (office), mobile: +1 703 29 2099; or Nils Hoffman, +1
703 820 2244 (office), mobile: +1 703 967 1490.
For UK Media enquiries, please contact Victoria Sabin or Julia Hobsbawn,
Hobsbawn Media and Marketing Communications, +44 207 964 8570 (office), or
Victoria Sabin, mobile + 44 07971 430244.
Nicolas Gaudin, Chief, IARC Communications, International Agency for Research
on Cancer, Tel: +33 472 738 567 Mobile : +33 680 572 966, Fax: +33 472 738 311,
E-mail: com@iarc.fr
Rebecca Harding, Communications Officer, World Health Organization, Mobile
(+41) 79 509 0651.
Please note that high resolution photos will be available on
WHO
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