Epidemiology of cancer

1. DR SUHAS.K.R
1

2. 
 Epidemiology is the study of the distribution and determinants of
health-related states or events in specified populations and the
application of this study to control health problems
 The oldest known description of human cancer is found in Egyptian
papyri written between 3000-1500 BC.
Two of them, known as the "Edwin Smith" and "George Ebers"
papyri, contain details of conditions that are consistent with
modern descriptions of cancer.
Introduction
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3. Cancer Epidemiology
Historical Perspective
1713 Bernardino Ramazzini, an Italian doctor - the virtual
absence of cervical cancer and relatively high incidence of breast
cancer in nuns
1775 - British surgeon, Percival Pott - probably the first description of
occupational carcinogenesis in the form of scrotum cancer among
chimney sweeps.
1950 - Lung cancer study conducted by Doll and Hill -
linked tobacco smoking to an increased mortality of lung cancer in
over 40,000 medical professionals in the United Kingdom
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4. 
Cancer Epidemiology
Historical Perspective
 Tobacco and Lung Cancer
 Asbestos and Lung Cancer
 Leather Industry and Nasal Cancer
 Dyes and Bladder Cancer
 Ionizing Radiation and Many Cancers
 DES and Vaginal Adenocarcinoma
 EBV and Burkitt’s Lymphoma
 HPV and Cervical Cancer
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5. 
Aims of Cancer Epidemiology
 Uncover new etiologic leads
 study of the distribution of cancer
 quantify the risk associated with different exposures and
host factors
 Promote insights into the mechanisms of carcinogenesis
 Assess efficacy of preventive measures
 Investigate predictors of survival
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6.  The Surveillance, Epidemiology, and End Results (SEER)
Program of the National Cancer Institute (NCI) - an
authoritative source of information on new cancer cases and
cancer survival in the United States.
Case ascertainment for SEER began in 1973
 The World Health Organization's International Agency for
Research on Cancer and the International Association of Cancer
Registries publishes Cancer Incidence in Five Continents
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7. 
Cancer Epidemiology
Sources
 US SEER Registry System
 IARC International Registries
 State/Hospital Registries
 Etiologic Clues
 “Alert” Clinician
 Experimental Studies
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8. 
Study designs
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9. 
Methods of Cancer Epidemiology
 Descriptive Studies
 Incidence, mortality, survival
 Time Trends
 Geographic Patterns
 Patterns by Age, Gender, SES,
Ethnicity
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10. 
 a global perspective on cancer is critical
 The huge international variation in the occurrence of many
types of cancer
 worldwide burden of cancer is no longer confined
predominantly to the industrialized, wealthy countries
 The impact of migration on cancer rates
Global Cancer Incidence (Surveillance,
Epidemiology, and End Results Database)
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11. 
 Incidence and Mortality Rates
quantify the number of newly diagnosed cancer cases or
deaths, respectively, in a specified population over a defined time
period
 Prevalence
the rate at which new cancer cases are diagnosed in a
specified population and time interval, measures the number or
percentage of people in the population who are living after a
diagnosis of cancer.
Data Sources and Measurements
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12. 
 In addition to the effects of age, the overall risk of developing
or dying from cancers is affected by gender, socioeconomic
status, race/ethnicity and geographic location
 Sex
The incidence rates of most cancers that affect both men
and women are higher in men than women
few exceptions breast, thyroid, and gallbladder
Overall Cancer Risk
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13. 
 Socioeconomic Status
 Race and Ethnicity
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14. 
 Cancers that are strongly related to infectious etiologies, for
example, stomach, liver, and uterine cervix are, in general,
decreasing globally
 Rapid increase in the occurrence of malignancies that were
historically common only in wealthy countries, but that now
are increasing in middle- and low-resource countries - include
cancers of the lung, breast, prostate, and colon/rectum.
Temporal Trends
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15. 
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16. 
Indian scenario-ICMR DATA
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17. 
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18. 
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19. 
 A comparison of inter registry rates showed that among males, lung
cancer was the leading site in Bhopal, Delhi and Mumbai while it was the
second leading site in Chennai and Bangalore.
 Cancer of the stomach was the leading site in Chennai and Bangalore,
whereas, it occupied different positions in other registries.
 In Barshi, cancer of oesophagus occupied the leading site.
 Tongue and mouth - the leading site of cancer in Ahmedabad registry.
Comparison
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20.  In females, breast cancer was the leading site of cancer in all
registries except Barshi
 This was followed by cancer cervix as the second leading site of
cancer.
 Ovarian cancer occupies the third leading site in Delhi, Mumbai,
Chennai, Bhopal and Ahmedabad registry while it was placed
fourth and fifth in Bangalore and Barshi respectively.
Comparison
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21. 
Ten Leading Sites of Cancer - Delhi
Males
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22. 
Ten Leading Sites of Cancer -
Delhi
females
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23. 
23

24. 
Number(#) & Proportion(%) of specific sites of
cancer among all
Tobacco Related Cancers (TRC)
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25. 
Number(#) & Proportion(%) of specific sites of cancer
among all
Tobacco Related Cancers (TRC)
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26. 
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27. 
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28. 
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29. 
 Worldwide, lung cancer - the most common cancer in terms of both
newly diagnosed cases and deaths
 The highest rates are among men in eastern Europe, North America,
and the rest of Europe, whereas the lowest rates are observed in Africa,
excluding South Africa
Lung Cancer
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30. 
 Lung cancer - more strongly associated with cigarette smoking
than any other cancer site. Globally, an estimated 85% of lung
cancers in men and 47% in women
 Cigarette smoking is estimated to have killed 100 million
people in the 20th century, and is projected to kill one billion
people in the 21st century, unless smoking patterns change
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31. 
trends
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32. 
The joinpoint trend in SEER cancer incidence with associated APC(%) for cancer of the lung and bronchus
between 1975-2010, All Races
Male and Female Male Female
Trend Period Trend Period Trend Period
2.5* 1975-1982 1.4* 1975-1982 5.6* 1975-1982
1.0* 1982-1991 -0.4 1982-1991 3.4* 1982-1991
-0.7* 1991-2007 -1.8* 1991-2010 0.5* 1991-2007
-2.6* 2007-2010
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33. 
 Based on rates from 2008-2010, as 1 in 15 men and women will
be diagnosed with cancer of the lung and bronchus during their
lifetime.
Lifetime Risk
Stage Distribution and 5-year Relative Survival by Stage at Diagnosis for
2003-2009, All Races, Both Sexes
Stage at Diagnosis
Stage
Distribution (%)
5-year
Relative Survival (%)
Localized (confined to primary
site)
15 53.5
Regional (spread to regional
lymphnodes)
22 26.1
Distant (cancer has metastasized) 57 3.9
Unknown (unstaged) 6 7.8
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34. 
 Among women, breast cancer is the most frequently diagnosed
cancer and the leading cause of cancer death worldwide
Female Breast Cancer
34

35. 
 Factors that contribute to the striking international variation -
historical differences in reproductive factors (age at menarche,
menopause, and first live birth and number of children), use of
hormone-replacement therapy, obesity after menopause,
alcohol intake, and screening practices.
 Based on rates from 2008-2010, 1 in 8 women will be diagnosed
with cancer of the breast during their lifetime
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36. 
The joinpoint trend in SEER cancer incidence with
associated APC(%) for cancer of the breast between
1975-2010, All Races
Female
Trend Period
-0.5 1975-1980
4.0* 1980-1987
-0.2 1987-1994
1.8* 1994-1999
-2.3* 1999-2004
0.1 2004-2010
The joinpoint trend in US cancer mortality with
associated APC(%) for cancer of the breast
between 1975-2010, All Races
Female
Trend Period
0.4* 1975-1990
-1.8* 1990-1995
-3.2* 1995-1998
-1.9* 1998-2010
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37. 
 Cancers of the colon and rectum (colorectal cancer) are the
fourth most common cancer diagnosed in men and the third
most common in women
Colon and Rectum Cancer
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38. The joinpoint trend in SEER cancer incidence with associated APC(%) for cancer of the colon and rectum
between 1975-2010, All Races
Male and Female Male Female
Trend Period Trend Period Trend Period
0.8* 1975-1985 1.1* 1975-1985 0.3 1975-1985
-1.8* 1985-1995 -1.2* 1985-1991 -1.9* 1985-1995
1.5 1995-1998 -3.2* 1991-1995 1.8 1995-1998
-2.3* 1998-2008 2.0 1995-1998 -2.0* 1998-2008
-5.1* 2008-2010 -2.8* 1998-2008 -5.1* 2008-2010
-4.8* 2008-2010
Based on rates from 2008-2010, 1 in 21 men and women
will be diagnosed with cancer of the colon and rectum
during their lifetime.
38

39. 
Stage Distribution and 5-year Relative Survival by Stage at Diagnosis for
2003-2009, All Races, Both Sexes
Stage at Diagnosis
Stage
Distribution (%)
5-year
Relative Survival (%)
Localized (confined to primary
site)
40 90.3
Regional (spread to regional
lymphnodes)
36 70.4
Distant (cancer has metastasized) 20 12.5
Unknown (unstaged) 5 33.6
1 in 21 men and women will be diagnosed with cancer of the colon
and rectum during their lifetime.
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40. 
The joinpoint trend in SEER cancer incidence with associated APC(%) for cancer of the oral cavity and
pharynx between 1975-2010, All Races
Male and Female Male Female
Trend Period Trend Period Trend Period
0.7 1975-1981 -0.1 1975-1983 3.4 1975-1979
-1.1* 1981-2003 -1.5* 1983-2001 -0.8* 1979-2010
0.4 2003-2010 0.2 2001-2010
Oral cavity
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41. 
Stage Distribution and 5-year Relative Survival by Stage at Diagnosis for
2003-2009, All Races, Both Sexes
Stage at Diagnosis
Stage
Distribution (%)
5-year
Relative Survival (%)
Localized (confined to primary
site)
31 82.7
Regional (spread to regional
lymphnodes)
47 59.2
Distant (cancer has metastasized) 17 36.3
Unknown (unstaged) 6 49.3
1 in 92 men and women will be diagnosed with cancer of the oral
cavity and pharynx during their lifetime
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42. 
Prostate - second most frequently diagnosed cancer and the sixth
most common fatal cancer among men worldwide
The joinpoint trend in SEER cancer incidence with
associated APC(%) for cancer of the prostate
between 1975-2010, All Races
Male
Trend Period
2.6* 1975-1988
16.5* 1988-1992
-11.6* 1992-1995
2.4 1995-2000
-2.0* 2000-2010
The joinpoint trend in US cancer mortality with
associated APC(%) for cancer of the prostate
between 1975-2010, All Races
Male
Trend Period
0.9* 1975-1987
3.1* 1987-1991
-0.8 1991-1994
-3.8* 1994-2004
-3.1* 2004-2010
42

43. 
Stage Distribution and 5-year Relative Survival by Stage at Diagnosis
for
2003-2009, All Races, Males
Stage at Diagnosis
Stage
Distribution (%)
5-year
Relative Survival (%)
Localized (confined to
primary site)
81 100.0
Regional (spread to
regional lymphnodes)
12 100.0
Distant (cancer has
metastasized)
4 27.9
Unknown (unstaged) 3 72.9
1 in 7 men will be diagnosed with cancer of the prostate
during their lifetime
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44. 
Worldwide incidence of prostate cancer -incidence
trends largely by rates of PSA screening
44

45. The joinpoint trend in SEER cancer incidence with associated APC(%) for cancer of the kidney and renal
pelvis between 1975-2010, All Races
Male and Female Male Female
Trend Period Trend Period Trend Period
2.3* 1975-1994 1.8* 1975-2004 2.7* 1975-1994
-0.6 1994-1997 4.2* 2004-2008 -0.9 1994-1997
3.2* 1997-2008 -3.0 2008-2010 3.4* 1997-2008
-3.4 2008-2010 -6.1 2008-2010
Kidney
The joinpoint trend in US cancer mortality with associated APC(%) for cancer of the kidney and renal pelvis
between 1975-2010, All Races
Male and Female Male Female
Trend Period Trend Period Trend Period
1.0* 1975-1994 1.1* 1975-1991 1.1* 1975-1994
-0.6* 1994-2010 -0.1 1991-2001 -0.9* 1994-2010
-0.9* 2001-2010
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46. 
Stage Distribution and 5-year Relative Survival by Stage at Diagnosis for
2003-2009, All Races, Both Sexes
Stage at Diagnosis
Stage
Distribution (%)
5-year
Relative Survival (%)
Localized (confined to primary
site)
63 91.7
Regional (spread to regional
lymphnodes)
17 64.2
Distant (cancer has metastasized) 17 12.3
Unknown (unstaged) 3 33.5
1 in 62 men and women will be diagnosed with cancer
of the kidney and renal pelvis during their lifetime
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47. 
cervix
The joinpoint trend in SEER cancer
incidence with associated APC(%) for
cancer of the cervix uteri between 1975-
2010, All Races
Female
Trend Period
-4.6* 1975-1982
-0.2 1982-1990
-2.5* 1990-2010
The joinpoint trend in US cancer
mortality with associated APC(%) for
cancer of the cervix uteri between 1975-
2010, All Races
Female
Trend Period
-4.3* 1975-1982
-1.6* 1982-1996
-3.7* 1996-2003
-1.1* 2003-2010
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48. 
Stage Distribution and 5-year Relative Survival by Stage at Diagnosis for
2003-2009, All Races, Females
Stage at Diagnosis
Stage
Distribution (%)
5-year
Relative Survival (%)
Localized (confined to primary
site)
47 90.9
Regional (spread to regional
lymphnodes)
36 57.1
Distant (cancer has metastasized) 12 16.1
Unknown (unstaged) 4 54.3
1 in 151 women will be diagnosed with cancer
of the cervix uteri during their lifetime
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49. 
Worldwide incidence
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50. 
 The burden of cancer worldwide varies across countries according
to differences in risk factors, detection practices, treatment
availability, age structure, and completeness of reporting.
 Cancers related to infections account for about 28% of the cases in
developing countries and less than 8% of the cases in developed
countries.
Conclusion
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51.  Cancers in developing countries more often result in death - generally
diagnosed at late stage and the resources for early detection and
treatment limited.
 21% of the world population (most of whom are in the more affluent
world) is covered by population-based cancer registries with high-
quality incidence data for only 9% of the world population
 expansions of registries in geographic coverage, quality, and scope
will be a necessary step in promoting cancer control programs
worldwide.
Conclusion
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52. Thank you
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