Download Cancer Atlas, 2nd edition Major risk factors for cancer

Cancer Atlas, 2nd edition
Major risk factors for cancer
Prof Paolo Vineis
Imperial College London
Session code: CTS.4.230
www.worldcancercongress.org
Cancer as a multifactorial process
The Hallmarks of Cancer
From D Hanahan, The Lancet, February 8, 2014
Genes or environment?
Stomach cancer incidence in Hawaii Japanese and
Caucasians by place of birth, 1973-77
Heredity Can Affect Many Types of Cancer
Inherited Conditions That Increase Risk for Cancer (5-10% of
cases)
Heritability of Colorectal Cancer
Familial
High
Penetrance
APC (FAP),
MMR
(Lynch),
TGFβR2,
POLD,
SMAD4
(Familial
CRC)
Sporadic
Low Penetrance
8q23, 8q24, 10p14,
11q23, 14q22, 15q13,
18q21 (SMAD7), 19q31,
20p12, GSTM1
null, NAT2 G/G
Modifier Alleles
Genes
Environment
2
Smoking is associated with at
least 16 types of cancers.
Nasal cavity
and
paranasal
sinus
Oral
cavity
Laryn
x
Pharynx
Esophag
us
Bone
marrow
(acute
myeloid
leukemia)
Cancer can be
caused by a variety
of known risk
factors, many of
them preventable.
3
43%
Exposure to
betanaphthylamine
Liv
er
23%
Stoma
ch
1
80—
RATE PER
100,000
60—
40—
Rates in
Japanese
Hawaiians are
more similar to
cancer rates of
white
Hawaiians,
rather than
Japanese
23.9
in22.4
Japan.
Japanese
20—
in Hawaii
6.3
91.4
13%
0.7%
General
male
populatio
n
Colon
Cancer
Ovari
es
Cerv
ix
Benzidine
manufactur
e
Mixed exposure
to carcinogenic
amines
40
30
20
10
0
1.
Be as lean as possible
without becoming
underweight.
2.
Be physically active for at
least 30 minutes every
day.
3.
Avoid sugary drinks.
Limit consumption of energy-dense foods
(particularly processed foods high in
added sugar, low in fiber, or high in fat).
4.
Eat a variety of vegetables,
fruits, whole grains, and pulses
such as beans.
ESTIMATED HPV PREVALENCE (%), ALL TYPES COMBINED, AMONG
WOMEN BY REGION, 1995-2009
5.
Limit consumption of red
meats (such as beef, pork
and lamb) and avoid
processed meats.
6.
Limit alcoholic drinks
to 2 drinks per day for
men and 1 drink per day
for women.
14%
Europe
9%
Asia
16%
7.
Limit consumption of salty
foods and foods processed
with salt (sodium).
21%
Latin America &
the Caribbean
Hawaii
Whites
50
4
Northern America
34.9
60
The World Cancer Research Fund
(WCRF/AICR) has released (and
periodically updates) guidelines for
cancer prevention:
Compared with Northern America, the estimated prevalence of human papillomavirus
(HPV), the leading cause of cervical cancer, is about three times as high in Europe
and Latin America, and four times as high in Africa.
5%
Africa
17.4
Japanese
in Japan
0—
Urinary
bladder
Dietary recommendations from
the WCRF/AICR
90
70
Uret
er
Colorect
um
100—
100
80
Kidne
ys
CANCER INCIDENCE AGESTANDARDIZED RATES
(WORLD) PER 100,000, CIRCA
1970
Distillers of
betanaphthylamine
Lungs
Pancre
as
Cancer is more often caused by the
environment a person lives in, rather
than his or her innate biology.
5
100%
Increasing intensity of occupational
exposure to carcinogens carries
increasing risk of developing cancer.
8.
Don’t use supplements to protect
against cancer. Instead, choose a
balanced diet
with a variety of foods.
Human papillomavirus types 16 and 18 are the most prevalent types of
HPV worldwide,
Stomach Cancer
accounting for over 70% of all cervical cancer
cases.
19
Tobacco Use and Cancer
Cancer sites for which there is “sufficient” evidence of carcinogenicity of tobacco smoking according to the
IARC Working Group: number of studies on which the evaluation was based and average relative risk.
CC=case-control
Cancer site
Lung
Urinary tract
Upper aero-digestive tract:
Oral cavity,
Oro-and hypopharynx
Oesophagus
Larynx
Pancreas
Stomach
Liver
Kidney
Uterine cervix
Number of studies
CC
Cohort
>100
37
50
24
RR
28
45
25
38
44
29
13
49
4-5
1.5-5
10
2-4
1.5-2
1.5-2.5
1.5-2.0
1.5-2.5
(Vineis et al, JNCI 2004 Jan 21;96(2):99-106)
6
19
5
27
27
29
8
14
15-30
3
Trends in Overweight and Obesity
WHO, 2010
Colorectal cancer and dietary fibre
S. Bingham et al. , The Lancet, May 21, 2003
RR estimate
1.0
corrected
upper limit
0.8
corrected
0.6
corrected
lower limit
0.4
0.2
10.0
15.0
20.0
25.0
30.0
35.0
40.0
fibre (g/day)
Statistical model adjusted for : energy, height, weight, physical activity,
alcohol and tobacco
SCFA!
Butyrate!
Lower pH!
Bacterial metabolism in colon!
Bacterial mass!
Apopotosis?!
Reduced transit
time, dilution,less !
mucosal contact!
Physical activity level around the world
Source: WHO
Cancer Research Fund) RECOMMENDATIONS
Be as lean as possible within the normal range of body weight
Be as lean as possible within the normal range of body weight
Be physically active as part of everyday life
Be physically active as part of everyday life
Limit consumption of energy-dense foods Avoid sugary drinks
Limit consumption of energy-dense foods Avoid sugary drinks
Eat mostly foods of plant origin
Eat mostly foods of plant origin
Limit intake of red meat and avoid processed meat
Limit intake of red meat and avoid processed meat
Limit alcoholic drinks
Limit alcoholic drinks
Limit consumption of salt
Avoid mouldy cereals (grains) or pulses (legumes)
Avoid mouldy cereals (grains) or pulses (legumes)
Aim to meet nutritional needs through diet alone
Aim to meet nutritional needs through diet alone
Mothers to breastfeed; children to be breastfed
Mothers to breastfeed; children to be breastfed
Follow the recommendations for cancer prevention
Follow the recommendations for cancer prevention
Infectious Agents and Cancer
agents worldwide
•  25% in Africa
•  <10% in Europe (1 in 33 in UK)
Agent
Cancer
HPV (16,18)
Cervix, Head and Neck
EBV
Hodgkin’s Lymphoma, Burkitts
HCV, HBV
Liver
H. Pylori
Stomach
Occupational Carcinogens
Some Carcinogens in the Workplace
Mesothelioma deaths by sex and year in England and Wales. From
Hodgson et al, 2005
Parkin’s estimate of preventable cancers
(Parkin et al, 2012)
=> 5 servings of fruit and vegetables; =>23 g/day of fibers; <=6 g/day of salt; BMI<=25 kgm-2;
physical activity=> 30 min 5 times/week; breastfeeding at least 6 months
14 risk factors and 18 cancer sites have been considered.
The result is that 45% of cancers in men and 40% in women could have been prevented had risk
factors been reduced to the optimal levels or eliminated (like tobacco).
Reduction/elimination of the same risk factors would lead to a substantial reduction also of cases of
cardiovascular disease, renal disease, hepatic disease, diabetes and possibly some neurological
diseases.
Advantages of primary prevention
(P Vineis, C Wild. Global cancer patterns: causes and prevention.The Lancet 2014 Feb 8;383(9916):
549-57)
Primary prevention decreases social inequalities, when it is effective. Current structural reforms
increase inequalities within/between countries
Primary preventive activities have an impact that go beyond those who are directly affected by it, for
example for an indirect effect.
The typical instance is herd immunity. Similarly, banning smoking in public places has a positive
effect not only in those potentially exposed to secondhand smoke (the target population), but also in
smokers, who will smoke less.
Prevention is usually effective on more than one disease (cancer CVD, diabetes, hypertension,
neurological diseases) and does not require to be renewed at each generation like therapies.
Threats to primary prevention
Primary prevention acts on exposures to risk factors.
An exclusively individualized approach is unlikely to have a strong
impact, while societal actions are more likely to be effective.
However, the tendency to reduce public expenditure and privatize
parts of the health care systems will impact on preventive activities
such as health promotion, which are not appealing for private
enterprises.
In the US, Europe and Canada less than 4% of the current public
budget is spent in cancer prevention (including all types)(Sullivan et
al, 2012)
The spread of the cancer epidemic to low-income countries should
and could be stopped now.
Thank you