World Burden of Cancer Epi 242 Cancer Epidemiology Binh Goldstein, Ph.D. October 7, 2009

Measures of Cancer Frequency: Incidence number of new cases occurring number of new cases occurring can be expressed as an absolute number of cases per year or as a rate per 100,000 persons per year. can be expressed as an absolute number of cases per year or as a rate per 100,000 persons per year. incidence rate provides approximation to average risk of developing a cancer and is necessary to compare risk of disease between populations incidence rate provides approximation to average risk of developing a cancer and is necessary to compare risk of disease between populations reduction in incidence is the appropriate statistics to use when considering impact of primary prevention strategies reduction in incidence is the appropriate statistics to use when considering impact of primary prevention strategies

Measures of Cancer Frequency: Mortality number of deaths occurring number of deaths occurring mortality rate is the number of deaths per 100,000 persons per year mortality rate is the number of deaths per 100,000 persons per year mortality rates measure average risk of dying from a specific cancer mortality rates measure average risk of dying from a specific cancer number of deaths is one measure of outcome or impact of cancer number of deaths is one measure of outcome or impact of cancer Fatality, (1-survival), is probability that an individual with cancer will die from it and is generally assumed to be most severe sequelae of disease Fatality, (1-survival), is probability that an individual with cancer will die from it and is generally assumed to be most severe sequelae of disease

Measures of Cancer Frequency: Prevalence NO agreed definition of “prevalence” of cancer NO agreed definition of “prevalence” of cancer number of persons in a defined population alive at a given time who have had cancer diagnosed at some time in past number of persons in a defined population alive at a given time who have had cancer diagnosed at some time in past partial prevalence limits number of patients to those diagnosed during fixed time in past and is more useful prevalence measure of cancer burden partial prevalence limits number of patients to those diagnosed during fixed time in past and is more useful prevalence measure of cancer burden prevalence for cases diagnosed within 1, 3, 5 years are likely to be of relevance to different stages of cancer therapy: initial treatment (1 year), clinical follow-up (3 years) and cure (5 years) prevalence for cases diagnosed within 1, 3, 5 years are likely to be of relevance to different stages of cancer therapy: initial treatment (1 year), clinical follow-up (3 years) and cure (5 years) patients still alive 5 years after diagnosis are considered “cured” since their death rates are similar to general population (some exceptions, like breast cancer) patients still alive 5 years after diagnosis are considered “cured” since their death rates are similar to general population (some exceptions, like breast cancer)

Other Measurements: Survival survival time defined as time that elapsed between diagnosis and death survival time defined as time that elapsed between diagnosis and death most basic measure of patients’ survival is the observed survival most basic measure of patients’ survival is the observed survival 5-year observed survival is percentage of patients alive after 5 years of follow-up from date of diagnosis 5-year observed survival is percentage of patients alive after 5 years of follow-up from date of diagnosis

Other Measurements: Relative Survival deaths from other competing causes will lower the observed survival rates and preclude comparison between groups where probability of death in the general population vary deaths from other competing causes will lower the observed survival rates and preclude comparison between groups where probability of death in the general population vary relative survival rate can be calculated to avoid this problem relative survival rate can be calculated to avoid this problem relative survival rate is observed survival rate in a patient group divided by expected survival of a comparable group in the general population with respect to age, sex, and calendar period of investigation relative survival rate is observed survival rate in a patient group divided by expected survival of a comparable group in the general population with respect to age, sex, and calendar period of investigation

Measures of Cancer Frequency How are the different measures related? How are the different measures related? M = I x F, where F is fatalityM = I x F, where F is fatality M ≈ I(1-S), where S is 5-year survivalM ≈ I(1-S), where S is 5-year survival P = I x D, where D is durationP = I x D, where D is duration F = (1-S)F = (1-S)

Other Measurements of Burden PYLLs (Potential Years of Life Lost) PYLLs (Potential Years of Life Lost) QALYs (Quality Adjusted Life Years) QALYs (Quality Adjusted Life Years) DALYs (Disability Adjusted Life Years) DALYs (Disability Adjusted Life Years)

Global Cancer Statistics

Incidence by sex and cancer site, World 2002 Source: Table 1: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Mortality by sex and cancer site, World 2002 Source: Table 1: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Estimated Age-adjusted Survival (%) Source: Table 2: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Incidence and prevalent cases, World 2002 Source: Figure 3: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

The Major Cancers Lung (ICD-10 C33 and C34) Lung (ICD-10 C33 and C34) Breast (female, C50) Breast (female, C50) Colon/rectum (C18-C20) Colon/rectum (C18-C20) Stomach (C16) Stomach (C16) Prostate (C61) Prostate (C61) Liver (C22) Liver (C22) Cervix uteri (C53) Cervix uteri (C53) Esophagus (C15) Esophagus (C15)

US More developed countries Less developed countries SiteMalesFemalesMalesFemalesMalesFemales Lung Breast─101.1─67.8─23.8 Colon/Rectum Stomach *10.0* Liver Prostate124.8─56.2─9.4─ Cervix─7.7─10.3─19.1 Esophagus Age Standardized Incidence Rates

World Age Standardized Incidence and Mortality Rates IncidenceMortality MalesFemalesMalesFemales Lung Breast─37.5─13.2 Colon/Rectum Stomach Liver Prostate25.3─8.2─ Cervix─16.2─9.0 Esophagus

Lung cancer 1.35 million new cases and 1.18 million deaths worldwide estimated in million new cases and 1.18 million deaths worldwide estimated in % new cases occurred in more developed countries (previously 69%) 50% new cases occurred in more developed countries (previously 69%) more common in males (2.9 male:female ratio) more common in males (2.9 male:female ratio) patterns of lung cancer occurrence determined largely by past exposure to tobacco smoking patterns of lung cancer occurrence determined largely by past exposure to tobacco smoking

Age-standardized incidence rates for lung cancer Source: Figure 5: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Lung cancer incidence trends in countries where smoking was first established (UK, US, Australia, etc.), rates declining among men in countries where smoking was first established (UK, US, Australia, etc.), rates declining among men in most other countries, rates rising in most other countries, rates rising rates in women generally increasing since tobacco habit is fairly recent, except in countries where their smoking prevalence is declining rates in women generally increasing since tobacco habit is fairly recent, except in countries where their smoking prevalence is declining

Lung cancer mortality trends similar to incidence trends similar to incidence trends

Breast cancer 1.15 million new cases and 410,000 deaths worldwide estimated in million new cases and 410,000 deaths worldwide estimated in 2002 most common cancer in women most common cancer in women Over half of new cases occurred in more developed countries Over half of new cases occurred in more developed countries stage of disease at diagnosis is most important prognostic factor stage of disease at diagnosis is most important prognostic factor most prevalent cancer in world because of its good prognoses most prevalent cancer in world because of its good prognoses risk increases with age but slows at about 50 years because of menopause and lower estrogen levels risk increases with age but slows at about 50 years because of menopause and lower estrogen levels

Age-standardized incidence and mortality rates for breast cancer Source: Figure 6: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Breast cancer incidence trends generally increasing at all ages generally increasing at all ages

Breast cancer mortality trends may be declining in recent years (like in US, Canada, and some European countries) due to screening and detection of early stage cancers and more effective treatment may be declining in recent years (like in US, Canada, and some European countries) due to screening and detection of early stage cancers and more effective treatment

Colorectal cancer About 1 million new cases and 529,000 deaths worldwide estimated in 2002 About 1 million new cases and 529,000 deaths worldwide estimated in rd most common cause of cancer in world but 2 nd most common in developed countries. 3 rd most common cause of cancer in world but 2 nd most common in developed countries. good prognoses (40-50% 5-year survival) makes it the 2 nd most prevalent cancer good prognoses (40-50% 5-year survival) makes it the 2 nd most prevalent cancer males and females have similar rates males and females have similar rates

Age-standardized incidence rates for colorectal cancer Source: Figure 7: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Colorectal cancer incidence trends increasing trend in low-risk areas increasing trend in low-risk areas stabilized or decreasing trends in high-risk areas stabilized or decreasing trends in high-risk areas greatest increases observed in Asia (especially Japan) and Eastern Europe (possibly from “westernization” of lifestyle/diet) greatest increases observed in Asia (especially Japan) and Eastern Europe (possibly from “westernization” of lifestyle/diet)

Colorectal cancer mortality trends decreasing trend in developed countries may be due to decreasing in incidence, improved treatment, and improvements in early detection (from screening) decreasing trend in developed countries may be due to decreasing in incidence, improved treatment, and improvements in early detection (from screening)

Stomach cancer 934,000 new cases and 700,000 deaths worldwide estimated in ,000 new cases and 700,000 deaths worldwide estimated in 2002 ranked 4 th in number of new cancers but 2 nd in most common cause of deaths from cancer ranked 4 th in number of new cancers but 2 nd in most common cause of deaths from cancer almost two-thirds of cases occur in developing countries almost two-thirds of cases occur in developing countries more common in males (1.75 male:female ratio) more common in males (1.75 male:female ratio) however, in younger age groups (<40 years) rates in women are greater than men however, in younger age groups (<40 years) rates in women are greater than men

Age-standardized incidence rates for stomach cancer Source: Figure 8: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Stomach cancer incidence trends general decline in rates among both developed and developing countries because of improved food preservation practices (refrigerators) and better nutrition (higher vegetable and fruit intake) general decline in rates among both developed and developing countries because of improved food preservation practices (refrigerators) and better nutrition (higher vegetable and fruit intake)

Stomach cancer mortality trends generally declining in both less and more developed regions generally declining in both less and more developed regions

Prostate cancer 679,000 new cases and 221,000 deaths worldwide estimated in ,000 new cases and 221,000 deaths worldwide estimated in nd most common new cancer and most prevalent form of cancer among males 2 nd most common new cancer and most prevalent form of cancer among males 75% of cases occur in men aged % of cases occur in men aged 65+ prostate-specific antigen assay introduced in mid to late ‘80s prostate-specific antigen assay introduced in mid to late ‘80s

Age-standardized incidence rates for prostate cancer Source: Figure 5: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Prostate cancer incidence trends in many developed countries incidence increased greatly, especially among younger men (<65 yrs) in many developed countries incidence increased greatly, especially among younger men (<65 yrs) most dramatic increases are in high-risk areas partly due to detection of prevalent latent cancers using PSA most dramatic increases are in high-risk areas partly due to detection of prevalent latent cancers using PSA less developed countries also increasing less developed countries also increasing

Prostate cancer mortality trends generally increasing but not as dramatically as incidence generally increasing but not as dramatically as incidence since 1990s, decline in several developed countries attributed to earlier detection and improved treatment since 1990s, decline in several developed countries attributed to earlier detection and improved treatment

Liver cancer 626,000 new cases and 598,000 deaths worldwide estimated in ,000 new cases and 598,000 deaths worldwide estimated in th most common cancer and 3 rd most common cause of deaths from cancer 6 th most common cancer and 3 rd most common cause of deaths from cancer 82% of cases occur in developing countries (55% in China) 82% of cases occur in developing countries (55% in China) male:female ratio is about 2.4 male:female ratio is about 2.4

Age-standardized incidence rates for liver cancer Source: Figure 10: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Liver cancer incidence trends difficult to interpret because of ICD revisions difficult to interpret because of ICD revisions 7 th revision includes gall bladder cancer7 th revision includes gall bladder cancer 9 th revision includes category of “unspecified 1 0 or 2 0 ”9 th revision includes category of “unspecified 1 0 or 2 0 ” ↓ among Chinese because of ↓ in prevalence of HBV ↓ among Chinese because of ↓ in prevalence of HBV ↑ in Japan because of ↑ alcohol consumption and HCV prevalence ↑ in Japan because of ↑ alcohol consumption and HCV prevalence ↑ in developed countries possibly from ↑ HCV infection (from transfusions and drug use) ↑ in developed countries possibly from ↑ HCV infection (from transfusions and drug use)

Liver cancer mortality trends similar to incidence trends similar to incidence trends increase in mortality among developed countries not necessarily from alcohol (since mortality from liver cirrhosis is decreasing) increase in mortality among developed countries not necessarily from alcohol (since mortality from liver cirrhosis is decreasing)

Cervical cancer 493,000 new cases and 274,000 deaths worldwide estimated in ,000 new cases and 274,000 deaths worldwide estimated in nd most common new cancer among women 2 nd most common new cancer among women 83% of cases occur in developing countries 83% of cases occur in developing countries rates are very low in developed countries rates are very low in developed countries generally, incidence rises at age and peaks around in developed countries, but usually later in developing countries generally, incidence rises at age and peaks around in developed countries, but usually later in developing countries

Age-standardized incidence and mortality rates for cervical cancer Source: Figure 11: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Cervical cancer incidence trends decreases in many developed countries because of screening programs decreases in many developed countries because of screening programs in developing countries, trends vary, but generally, rates (including mortality) are stabilized or decreasing in developing countries, trends vary, but generally, rates (including mortality) are stabilized or decreasing

Cervical cancer mortality trends decreases in many developed countries also because of diagnoses at earlier stages and improved treatment decreases in many developed countries also because of diagnoses at earlier stages and improved treatment

Esophageal cancer 462,000 new cases and 386,000 deaths worldwide estimated in ,000 new cases and 386,000 deaths worldwide estimated in % of cases occur in developing countries 84% of cases occur in developing countries generally, more common in males (male:female ratio over 2), but female predominance in some areas of “esophageal cancer belt” generally, more common in males (male:female ratio over 2), but female predominance in some areas of “esophageal cancer belt”

Age-standardized incidence rates for esophageal cancer Source: Figure 12: Parkin DM, et al. CA Cancer J Clin [2005]; 55:

Esophageal cancer incidence trends trends vary from increasing (Eastern Europe and US), stabilized (Southern Europe), to decreasing (Finland and China) trends vary from increasing (Eastern Europe and US), stabilized (Southern Europe), to decreasing (Finland and China)

Esophageal cancer mortality trends inconsistent trends like incidence inconsistent trends like incidence

Resources Garcia M, et al. Global Cancer Facts & Figures 2007, American Cancer Society, Garcia M, et al. Global Cancer Facts & Figures 2007, American Cancer Society, Ferlay J, et al. GLOBOCAN 2002 Database. Descriptive Epidemiology Group, International Agency for Research on Cancer, Ferlay J, et al. GLOBOCAN 2002 Database. Descriptive Epidemiology Group, International Agency for Research on Cancer, Parkin DM, et al. Global Cancer Statistics, CA Cancer J Clin, 2005; 55: Parkin DM, et al. Global Cancer Statistics, CA Cancer J Clin, 2005; 55: Parkin DM, et al. Cancer burden in the year The global picture. Eur J Cancer, 2001; 37 Suppl 8: S4-66. Parkin DM, et al. Cancer burden in the year The global picture. Eur J Cancer, 2001; 37 Suppl 8: S4-66.