world cancer report - iarc

PERSPECTIVES AND PRIORITIES
SUMMARY
> Current smoking levels and the adoption
of unhealthy lifestyles, together with a
steadily increasing proportion of elderly
people in the world, will result in a doubling
of new cancer cases, from 10 million
worldwide in 2000 to 20 million in
2020, with an annual death toll then
reaching 12 million.
> Strategies exist to reduce the predictable
burden of cancer through
research, education, prevention, early
detection, treatment and palliative care.
Political will and international collaboration
are now required for effective cancer
control.
> Application of existing knowledge, technology
and control strategies could prevent
at least a quarter of all cancer
cases, and cure at least a third of all
cancer cases in the next 20 years.
Thanks to social and economic advances
that the world has witnessed during the
late 20th century, humanity is facing rapid
change and many challenges. During the
last five decades, food supply has more
than doubled and increased much faster
than population growth; per capita gross
domestic product in real terms has risen
by at least two and a half times, and adult
literacy by more than 50% since 1970.
Dramatic increases have been observed in
the number and proportion of children at
school and the proportion of chronically
undernourished children has declined
considerably. These changes are having a
major impact on global disease patterns
and on the health and quality of life of
human beings. Without question, the face
of humanity is being rapidly reshaped due
to political, economic and sociocultural
interaction; the world of 2050 will be radically
different from today’s and will be
almost unrecognizable from that of 1950.
320 Cancer control
Population health is no exception to this
dynamic evolution, with global changes
influencing and conditioning the way individuals
and communities live, work and
age.
Increasing life expectancy and
population ageing
Globally, life expectancy at birth has
increased from 45 years in 1950 to 66
years in 2000 and is expected to reach
about 77 years in 2050 [1,2]. By 2025, the
majority of countries, covering about 96%
of total world population, will have a life
expectancy at birth of greater than 60
years; for no country will it be less than 50
years (Fig. 7.14). The global population is
expected to increase by 60% during the
next 50 years, from 6 billion people in
2000 to 9.4 billion people in 2050; the
number of people aged 60 years and
above will more than triple, from 610 million
to 1.9 billion, during this period.
With a slow and steady decline in fertility
rates, the population of the world is thus
ageing rapidly. The median age of the
global population will have risen from 23.5
years in 1950 to 36.5 years in 2050. The
global proportion of the population aged
60 years and over will increase from 10%
in 2000 to more than 20% in 2050. The
most rapid increase is, however, expected
among the number of “oldest-old” - those
aged 80 years and over. This population
will increase by a factor of five between
2000 and 2050. The number of centenarians
is increasing at an accelerating rate.
In France, for example, the estimated
number of centenarians was about 200 in
1950, and 8,500 in 2000, and will reach
150,000 by 2050. The life span of many
individuals extends beyond the age of 115
in some countries.
In the early 1950s, the great majority of
the global population died before the age
of 50; today, the great majority is dying
after the age of 50. It has been estimated
that among 100 persons aged 20 years in
1955, at least 60 will be able to celebrate
their 65th birthday and that among 100
persons aged 20 years in 1995, at least
80 persons will have that privilege. This
represents an increase of more than 30%
in survival chances between the two generations
and has been achieved through
advances in medicine and public health, in
science and technology and above all in
the adaptation and application of medicoscientific
know- ledge for the improvement
of health for all. These advances
offer real hope for a longer, and hopefully
a healthier future for humankind [3].
While extending life expectancy is desirable
in itself, it is equally important that
increased expectancy is accompanied by
freedom from any prospect of years of
suffering as a consequence of chronic diseases,
pain or disability. Individuals are
becoming conscious about their health
expectancy, defined as life expectancy in
good health. Unfortunately, while much is
known about the determinants of population
health in terms of life expectancy,
very little is known about human longevity
- the maximum duration of an individual’s
life and its determinants.
Cancer trends and prognosis
WHO reported that in 2000 [4] there were
more than 6 million deaths caused by cancer,
i.e. about 12% of a total of more than
55 million deaths from all causes worldwide.
Infectious and parasitic diseases
accounted for about 26% and diseases of
the circulation for about 30% of total
deaths. During the period 1985-1997, the
number of deaths from cancer is estimated
to have increased by 35%, from 4.5 million
deaths in 1985 to 6.1 million deaths in
1997 [5] (Fig. 7.17). Deaths from circulatory
diseases increased by about 30%, from
11.5 million to 15.1 million. These increases
were not, however, geographically uniform.
From 1985 to 1997, in more developed
countries, there was a slight decline
in the number of deaths due to circulatory
diseases, but an increase of about 9% in
the number of deaths due to cancer.
During the same period, in developing
countries the number of deaths increased