Cancer Epidemiology
Breast Cancer general stats
- 1.68 million new cases and 0.5 million deaths worldwide estimated in 2012 - most common cancer in women - slightly more cases in less developed than in more developed reginos
Lung cancer general stats
- 1.83 million new cases worldwide - 1.59 million deaths worldwide estimated in 2012 - 58% new cases occurred in less developed regions. more common in males (2.5 X) - patterns of lung cancer occurrence determined largely by PAST exposures to tobacco smoking
Probability of dying from the four main NCDs between 30 and 70, comparing countries
- Highest in Russia and India - Higher among some African countries and south east asian countries
Types of Biomarkers and what are they used for
- genetic susceptibility markers - markers of exposure - markers of biological effects - tumor markers early detection and diagnosis monitor the effectiveness of therapy *predict the biological potential of cancer??** *for pharmacogenetic, determine who will likely benefit from the therapy*
Age standardized incidence and mortality rates comparing males to females worldwide
- males have about 2X the incidence and mortality of cancers for most popular cancer sites - colorectum is only 1.5X as much
US Lifetime probability of developing cancer for males and females
1 in 2 for males, 1 in 3 for females; controlling ....for other competing risks?
genotoxic and nongenotoxic mechanisms
1) Chomosome breakage, fusion, deletion lead to genomic damage 2) inflammation, Reactive oxygen species, epigenetic silencing, lead to altered signal transduction all lead to loss of proliferation control, resistnce to apoptosis, hypermutability --> cancer
Four major NCDs
1) cardiovascular diseases (46%) 2) cancers (22%) 3) chronic lung disease (11%) 4) Diabetes (4%). Deaths from these four diiseases account for 82% of NCDs and 55.6% of overall deaths.
Tissue based (Histology) Diagnostic Procedures
1) core biopsy - Core needle biopsy is the procedure to remove a small amount of suspicious tissue from the breast with a larger "core" (meaning "hollow") needle. 2) excisional biopsy, second highest - the entire abnormality or area of interest is removed. 3) resection, highest level, removal of the tissue use this as the gold standard for the diagnosis of cancer
cell-based (cytology) diagnostic procedures
1) exfoliated (pap smear, urine, etc) - get cells from he whole system 2) aspirated (fine needle aspiration) -- stick a needle into a tumor, focused on a specific region typically used for cancer screening, not used as gold standard. Tissue is the gold standard.
Classification of tumors
1) histological origin: most commonly dealing with epithelial cells - easy to turn cancerous because more exposure to environment and high turn over rate mesenchyme - bone, less commonly cancerous because not exposed as often to carcinogens 2) biological behavior - benign vs. malignant
Pathological Report
1) histological type, tumor stage, grade, other features (
Sequence of Investigation for Etiology of Disease
1. Formulating hypothesis 2. Testing hypothesis 3. Intervention a. Formulating hypotheses b. Testing hypotheses (case control, or cohort)\ c. Hypothesis generating d. Method of Difference - if compare two sets with defference frequences, then disease might be caused by a facto that is different between the two groups. e. Method of Agreement - single factor common in a number of circumstances in which a isase occures with a high frequency. f. Method of Concomitant Variation - quantitative change in the factor is associated with a quantitative change in the effect g. Consideration in the Formation of Hypotheses i. Biological basis and support of the hypothesis ii. New hypothesis are commonly formed by relating observations from several different fields (clinical, pathological, and laboratory observations) iii. The stronger a statistical association, the more likely it is to suggest a causal hypothesis.
US how many new cases per year
1.685 million, almost equal number in males and females
Projected demographic effects on cancer incidence and mortality
10 milliion more new cancer cases, million more new caner cases
Cancer statistics in 2012: # of new cases and # deaths
14.1 million new cases in 2012; 8.2 million deaths in 2012
Trends in cigarette smoking and lung cancer rate
1950 release oif surgeon general's report on tobacco and health; tobacco use decreasing among all race/ethnic groups, decreasing among males and females
Prostate Cancer general stats
2nd most common among men and 5th leading cause of death worldwide. 1.1 million men worldwide diagnosed with prostate cancer in 2012. 70% of cases occurring in more **developed countries** 75% occur in men 65+.
Ionizing and non-ionizing radiation
3-5% contribution. several neoplasms, acute and chronic myeloid leukemia, cancers of the breast
Proportion of cancer deaths attributable to cigarette smoking, adults 35 and older
30% of cancer deaths can be attributed to tobacco use
Colorectal Cancer general stats
3rd most common cancer in men, 2nd most common in women; 1.4 million new cases, .7 million deaths; 5-year survival rate 40-50%; one of the most prevalent cancers because fair prognosis. females have nearly the same rate as males (1.44)
Cervical Cancergeneral stats
528,000 new cases and 266,000 deaths worldwide estimated in 2012. 4th most common cancer and 4th leading cause of death from cancer in women. more serious in lesser developed regions (almost 9/10). more developed have screening
Liver Caner
752,000 new cases, 746,000 deaths woldwide in 2012. 6th most common cancer, 2nd most common cause of deaths from cancer. 83% (50% in china alone) of new cancer cases occurred in less developed regions. male to female 2.83
Age Standardized Cancer Rate (ASR)
A summary measure of the rate that a population would have if it had a standard age structure. A weighted mean of age-specific rates. In order to compare populations with different age structures, because age has a powerful influence on risk of cancer.
What exactly is chemoprevention
Administering specific amounts of a particular natural or synthetic chemical in an attempt to identify agents that will prevent, halt or reverse the process of carcinogenesis. basic assumption: treating early stages of malignant process will halt the progression of malignancy the key is to define early lesions and treat malignant field
Intervention studies
Applying knowledge (risk/protective factors) obtained from analytic epidemiological studies to specific population in order to reduce the risk of cacner
Countries with highest incidence of colorectal cancer
Australia/New Zealand, and Western/Southern/Northern Europe
Leading Causes of Death in the US
Cancer =21% (females) 23.5% (males), Heart Disease = 22.4% (females) 24.6% (males)
What are the three most important confounders for cancer epidemiology
Cancer epidemiology, three most important confounding factors (risk factors). Must adjust for these major risk factors i. Age ii. Gender , very often stratify by gender Race
US cancer trends
Cancer leading cause of death among 45-64, In terms of number of deaths: heart disease fluctuating slightly increased since 1950, cancer constantly increasing and has almost surpassed heart disease.
Cervical Cancer Incidence and Mortality Rates
Common in Eastern African and Melanesia
Cancer Burden in the Future
Consider aging population, because of lower fertility and increased life expectancy
Infectious Agent
Considered the second most important factors ( ?) for cancer risk in the world. Nine infectious agents classified as group 1 carcinogens: EBV, HPV, HBV, HIV-1, HTLV-1, bacterium helicobacter pylori, parasites schistosoma, opisthorchis viverrni
Comparing country areas: # of new cancer cases
East Asia: 4 million plus Northern America: 1.8 million South-Central Asian: 1.5 million
Three major categories of cancer
Epithelial acncer - "Carcinoma" Mesenchyme - "Sarcoma" Hematopoitic - "Leukemia, Lymphoma"
Death Rates in African Americans compared to Whites by sites and sex
Essentially... African Americans have higher death rates in all (most?) sites in both sexes
IARC Carcinogen Classification: Group 4
Evidence suggesting lack of carcinogenicity. Evidence is consistent show that full range of dose does not cause cancer.
# of new cancer cases and deaths in low and middle-low income countries - are they different?
Expectedly, in middle-low and low income countries, # of new cancer cases and deaths similar
International variation in colorectal cancer incidence by sex (2012)
Females: high in Northern America, Western Europe, Australia, and Russia. Males: Same but only Canada and not Russia
Alcohol drinking
Group 1 carcinogen, sufficient evidence of carcinogenesis. high level increatses the risk of cancers of the oral cavity, pharynx, larynx, liver, pancreas, colorectum, female breast
Prostate Cancer Incidence/Mortality Rates
High in Australia/New Zealand, Northern America, Western Europe, Northern Europe
Which countries have high incidence rates of lung cancer?
High in US, West European countries, China, Australia For China: women have low prevalence of smoking, but may high rate may be due to indoor air pollution from unventilated coal-fueled stoves and cooking fumes
Countries/regions with high incidence mortality rates for Breast Cancer
High in Western Europe, North America, Northern Europe, Australia, but mortality rate around the same comparing all regions, some areas (like Western Africa) with low incidence rate, have an even higher mortality rate
US Cancer death rates by race
Highest among black men and women, lowest among asian men and women
Risk Stratification
Identification of AT-RISK subject who are also SUSCEPTIBLE to treatment. 1) not at risk of developing disease 2) at risk of above, but not responsive to agent X 3) at risk of developing disease, bio B, responsive to agent X
IARC Carcinogen Classification: Group 3
Inadequate evidence. Studies are of insufficient quality, consistency or statistical power to permit a conclusion regarding the presence or absence of a causal relationship. This group needs more studies.
Stomach Cancer Trends
Incidence decreasing overall, fresh fruits vegetables, decrease of salted and presered foods, mortality decreasing as well
Colorectal trends
Incidence increasing slightly in some countries; staying the same in others; and decreasing in US for both sexes, Mortality decreasing slightly for most countries
Prostate cancer trends
Incidence: Countries with higher uptake of PSA, with a rapid rise in 1990s followed by a sharp decline, other countries with low prevalence of PSA test do not show such a trend. Mortality: Declining in developed countries due to earlier detection and improved treatment.
Why is cancer a major public health problem?
Increasingly aging population worldwide, and cancer is generally considered an aging disease
Fruit consumption and vegetable consumption
Less in states in the South,
IAR Carcinogen Classification: Group 2 (a and b)
Limited evidence. A positive causal association has been observed, but chance, bias, confounding cannot be ruled out. i. 2a: Evidence in humans is limited, agent is an experimental carcinogen ii. 2b: same as above, except evidence in humans is deemed "inadequate of non-existent)
Proteomics
Looking at unique specto graph of proteins, and classifying them as diseased, health, or unclassificable. does not rely on the actual identification of proteins tumor generates signature proteins within he serum of cancer-affected patients
US cancer incidencce rate trends - race and sex
Males have higher rates overall Black males have highest, white females slightly higher than black females: breast and lung cancer among white females Asians have lowest rates
Most common cancer site worldwide by gender and country
Males: Most countries - prostate Eastern Europe, Russia, China - lung, bronchioles, trachea; Mongolia - liver Females: Most countries - breast cancer China - lung,bronchioles, trachea Mongolia - liver
New cancer cases in the US 2016, by gender
Males: 21% prostate, 14% lung and bronchus, 8% colon rectum Females: 29% Breast, 13% lung and bronchus, 8% colon rectum
Estimated Cancer Deaths in US 2016, by gender
Males: 27% lung bronchus, 8% prostate, 8% colon rectum Femaels: 26% lung bonchus, 14% breast, 8% colon rectum
The main distinction between benign and malignant tumor
Malignant tumor has invasion and metastatic potential whereas benign tumor does not. Malignant tumor has features of abnormal cellular differentiation whereas benign tumor usually does not
Trends of Incidence of Lung Cancer
Most countries - for men decreasing, for women increasing. Women's rates are still lower than men's. Increasing trend could be due to increased exposure to pollutants.
Trends of Mortality of Lung Cancer
Most countries similar to trends of incidence of lung cancer
US Cancer death rate trends among females by sites
Most decreasing, except for liver, see increase in lung and then decrease, less so than males' (less smokers)
SarcomaRsk
Muscle : smooth - Leiomysarcoma, skeletal - rhabdomyosarcoma Fat: Liposarcoma Skeleton- osteosarcoma cartilage - chondrosarcoma
Other minor categories of cancer
Nevocytic - "Melanoma" Germ cell - Teratoma, Seminoma, Yolk sac tumor Endocrine/Neuro - Carcinoid,INsulinoma/small cell carcinoma
Problem and need with morphology-based diagnosis, including cytology and histology
No better alternative. 1) low sensitivity - false negative findings 2) qualitative and ambiguity 3) not a functional test for cancer cell behavior (metastatic/invasive potential) 4) limited value to guide personalized management/precision medicine current approach only indirect information, can only analyze dead cells. cannot see cell behavior. small "innocent" lesions can be deadly. large aggressive looking tumor cells may have good response to cancer therapy.
NCD (proportion)
Non-Communicable Diseases - Worldwide, more than 2/3 of deaths due to NCD's (out of 58 million deaths that occurred in 2012, 38 million (68%)) - number has increased every year since 2000. - Projected to be 52 million by 2030 - For those under age 70, account for around half (52%
Cancer Mortality and Cancer Fatality
Number of deaths occurring in a given period in a specified population (A rate). (1-survival), a proportion of cancer patients who died from that specific cancer.
Cancer Incidence
Number of new cancer cases arising in a given priod, reduction in incidence rate is the appropriate statistics to use when evaluating the impact of primary prevention strategies.
Cancer Incidenece
Number of new cases, used to estimate risk for a specified population
Cancer Prevalence
Number of people living with a specific type of cancer in a defined population at any point in time
Current Clinically used Tumor Markers
PSA - prostate aenocarcinoma, Alpha FP - Hepatoma, seminoma, HCG - choreocarcinoma, problem: low sensitivity/specificity CEA - colon cancer, CA125 - ovarian cancer
Other measurements of cancer burden
PYLLs (the average years a person would have lived if he or she had not died prematurely), DALYs (number of years lost due to ill-health, disability, or early death), QALYs.
Unique features of chemoprevention
Participants are usually health or at least "cancer free", the degree and incidence of side effects that are acceptable are low. The end point is disease prevention not disease response. The incidence of the study end point is low.
Cancer Survival
Proportion of patients alive at some point (usually 5 years) after cancer diagnosis.
Retinoblatoma gene and P53 gene
RB is the most critical checkpoint in cell cycle, p53 most common genetic changes a negative regulator of cell division.
How does DNA methylation affect cancer
Silencing of tumor suppressor gene through hypermethylation which leads to transcriptional repression of tumor suppressor gene. OR activates proto-oncogenes. Through hypotmethylation, leads to increase oncogene expression
IARC Carcinogen Classification: Group 1
Sufficient evidence: A positive causal relationship has been established between exposure and occurrence of cancer.
Field Cancerization
The whole field of tissue of a particular organ is exposed to the carcinogenic insult anc is at increased risk for developing cancer. Although only a few foci eventually develop malignancy, the other areas are not necessarily entirely normal. Th most common epithelia cancers are developed through this mechanism. (the whole head/neck/bladder/breast is exposed)
Descriptive Epidemiology
To describe difference in occurrence of a particular cancer between different groups,and to generate hypothesis for increased/decreased rate for the specific tumor type.
Analytic Epidemiology
To study risk factors or potential causes of cancer by a particular study design, e.g. case control study or cohort study
Cancer site with highest incidence and deaths worldwide, by gender
Top new cases: lung for males and breast for females Top deaths: lung for males and breast for females
Three types of Cancer Intervention, purpose, and examples
Treating Premalignant lesion 1) Surgical procedure (castration) 2) Non-surgical (chemoprevention) (BCG, vaccine) 3) behavioral (smoking cessation)
Pap Test and Colposcopy
Used to detect and/or treat for cervical cancer
Neoplasm
abnormal growth of cells aka tumor "new" "Thing formed"
High throughut techniques *"omics"
array technology - DNA chips, protetomics, tissues arrays -- I don't know what this is
What are the three types of study designs for descriptive epidemiology?
b. Three types of study design for descriptive espidemiology i. Case report and case-series study to make inferences about individual level ii. Correlation study or ecologic study are at population level Cross-sectional study design at the individual level.
Leading type of cancers among new cancer cases worldwide
both: 1) breast 2) lung 3) colorectum female: 1) breast 2) colorectum 3) lung male: 1) lung 2) prostate 3) colorectum
Cancer mortality by sex and site worldwide (Top 3) by gender
both: 1) lung 2) liver 3) stomach males: 1) lung 2) liver 3) stomach females: 1) breast 2) lung 3) colorectum
US Top leading causes of death
both: ) lung 2) colorectal 3) pancreas; males 1) lung, 2) prostate 3) colorectal; females: 1) lung 2) breast 3) colorectal
US number of cancer deaths, life expectancy, and death rate in 2014
cancer: 584,881 in 2014 life expectancy: 78.8 years Death rate: 821.5 deaths per 100,000 population
Observed surivival
cannot compare survival proportions between groups with varying mortality rates, due to competing causes.
US more trends
decreasing death rate, but increasing cancer deaths because of aging and growing US population
Liver Cancer trends
decreasing incidence in countries with high rates before. reduced prevalence of HPV, and less exposure to risk factors increasing in some countries with historically really low rates, thought to be related to increased prevalence of HCV infection, or increased prevalence of obesity and diabetes.
Cervical Cancer trends
decreasing overall because of improved screening and SES conditions
Esoph. cancer trends
decreasing squamous - reduction of alcohol and tobacco use, increasing trend of adenocarcinoma, increasing prevalence of obesity/overweight
Phase II objectives and design
determine side effects, optimal recruitment methosd of population, retention of study participants, to determine optimal methos for conducting phase III tria, to determine effect of iintervention on biomarkers of carcinogenesis randomized, double blind, placebo controlled, multiple dose, 1-5 years, 100-1000
Phase III trial
determine the effect of the intervention on the cancer incidence, on death rate and disease incidence, long-term effects of intervention, nature history of specific biomarkers (placebo group) and the effect of the intervention agent on these markers (treatment group) 5-10 years, 1000-10,000
early stage vs. late stage carcinogens
early longer (response), late shorter (response) may not necessarily relate to the stages of initiation, promotion, and progression
Diet and obesity
exact role of dietary factors in causing/protecting human cancer remains largely unquantified, evidence of weight gain, high intake of red meat, exposure to aflatoxin
US top leading cancers
females: 1) breast 2) lung 3) colorectum males: 1) prostate 2) lung 3) colorectum both: 1) breast 2) lung 3) prostate
Breast Cancer, Cervical Cancer, and Colorectal Cancer Screening prevalence by race/ethnicity and insurance status
generally the same for most races; less screening prevalence among uninsured.
cancer death rates comparing black male and female
greatest difference in rates compared to other races
Cigarette smoking, adults 25 years and older by education
highest among those with GED, higher the degree, lower the prevalence of smoking
Esophageal cancer stats
highest male to female ratio (2.9), 80% of cases occur in less develop regions female predominance belt (Northern Iran through central Asian rebpulics to North Central China two major subtypes: squamous cell carcinoma (middle or upper third of esoph) - alcohol; adenocarcinoma (lower third or junction of the esophagus and stomach) -overweight/obese stomach reflux
What are the patterns of age-specific cancer incidence rates in humans?
i. 2: etiologic factors are strongest in early life; diminished exposure to exogenous agent at old age ii. 3: bimodal, different etiologic factors iii. 4: liver cancer, exposure to HBV from mother, age of diagnosis iv. 5: leukemiam childhood leukemia, and one after 6: some cancer rates dont change across age groups
Changes of cancer rates may be caused by many factors
i. Changes in diagnostic techniques ii. Changes in accuracy of tumor registry iii. Changes in age distribution may cause the increase in crude rates iv. Changes in survivals v. Improved treatment
what is descriptive epidemiology?
i. Concerned with the distribution of disease 1) What population/subgroups get the disease? a) Gender b) Race c) Marital status 2) In what geographic location it is most or least common 3) How the frequency of occurrence varies over time a) Seasonal changes
What are the three type of tests for identifying carcinogens?
i. Three types of tests 1) Long-term in experimental animals, usually rodents 2) Short-term tests assessing effect of chemical agents on a variety of endpoints belonging to generally three classes: DNA damage, mutagenicity, chromosome change. 3) Mechanistic tests: aimed at identifying intermediate steps in the compound-specific carcinogenic process ii. Comments 1) Sometimes there is no epidemiological evidence, only results from lab tests on animals, therefore they become all the more essential 2) IARC used a system of creating experts to evaluate carcinogens: example is alcohol and breast cancer; if there is no epi data, can look at all the available scientific evidence 3) Sometimes can use pooled analysis and don't need experts.... 4) EPA first defined smoking as a carcinogen
Globocan 2012 (not to memorize)
important website to do cancer research, has all the worldwide cancer statistics, by country, releases data every five years.
two stage theory of carcinogenesis
initiation and promotion, formally defined in a murine skin carcinogenesis mode: treated with a single dose of polycyclics aromatic hydrocarbon (initiator), followed by repeated topical doses of croton oil (promoter) problem: only applies to a certain type of carcinogenesis, does not take into account long latency periods of other kinds of cancers
Progression
irreversible stage with demonstrated changes in the structure of the genome of the neoplastic cells. changes are related to increased growth rate, metastatic capability and biochemical changes of the neoplastic cell.
Initiation
it is permanent and irreversible. first critical carcinogenic event usually a reaction between carcinogen (radiation, virus, chemical) and DNA
misclassification and cancer studies
it may be easy to misclassify exposures if exposures have changed over time
Precursors
lesion which may or may not include abnormal clones. should be defined to help with prevention.
Tissue Array
lookig at protein experssion patterns in a large number of indvidiual tissues for rapid and comprehensive molecular rofiling of cancer and oter diseases, withohhhhhut exhasuitng imited tissue resources??
obesity prevalence trends
majority less than 50% to 2010 all states greater than 55%
Stomach cancer general stats
more common in lesser developed areas (70% of cases), half the world total occurred in eastern asia, mainly in China. More common in men, but rates are equal or greater in youunger age group (<40 years). Almost one million new cases and 723,000 deaths worldwide. 5th most common cancer and 3rd leading cause of death from cancer.
US Cancer death rate trends males by sites
most decreasing, except liver and pancreas, see huge increase in lung and then decrease (less smokers)
Promotion
non in itself a carcinogen, but enhances the carcinogenicity of an agent. reversible and unstable
US skin cancer-related behaviors
not generally common to apply sunscreen (33%)
Complete prevalence vs. Limited-duration prevalence
number of patients alive at certain point who previously had a diagnosis of cancer (diagnosis before, or patients still under treatment) number of cancer patients daignosed during a fixed time in the past, usually 5-year considered cured.
Three leading causes of death worldwide by income level (overall, low and middle, high income)
overall: 1) cardiovascular diseases 2) malignant neoplasms 3) infectious and parasitic diseases low and middle: 1) Cardiovascular diseases 2) infectious and parasitic diseases 3) malignant neoplasms high-income: 1) cardiovascular diseases 2) malignant neoplasms 3) respiratory diseases
Coal Tars
phenols, PAHs, heterocyclic compounds
Premalignancy
reversible, cells can be differentiated back to normal. simplified model: normal -> premalignancy -> invasion metastasis. Cannot do much during metastasis stage.
US trends in cancer incidence rates males
sharp increase and decrease of prostate cancer incidence rate around 1990s due to changing patterns of utilization of PSA blood testing , slightdecrease of lung and colorectal, slight increase of urinary bladder, liver, thyroid melanoma
US trends in cancer incidence rates females
slight reduction of breast cancer incidence rate early 2000s, likely due to the reduction of hormone replacement therapy
US cancer incidence and death rates trends, by gender and race (black and white)
slightly increasing, males sharp increase and decrease around the 1990s due to PSA testing, first black males, then white males, then white females, then black females (close 4th) Although incidence slightly increasing, death rates slightly decreasing: first black males, then white males, then black females, then white females
Genetic factors
some genes dramatically increase the risk of some, but the number of cases attributable to them is small, estimated that about 10-30 percent of cancers are associated with genetic factors
Carcinoma subcategories
squamous - squamous cel carcinoma glandular - adenocarcinoma transitional - transitional cell carcinoma small cell - small cell carcinoma
Tobacco Smoking
the single major cause of human cancer worldwide, related cancers of the lung, nasal cavity, larynx,oral cavity, pharynx, esophagus, stomach, liver, pancreas, colorectum, ovary, uterine rcervix, kidney, and bladder.
Intermediate End Point Marker (Surrogate End Point Marker)
these are prevention biomarkers which are specifically related to early stages of cacinogenesis These markers are used to identify individual's risk for developing cancer and to monitor the effectiveness of intervention methods
multistage carcinogenesis
three stages: initiation, promotion, and progression
Phase I objective and design
to determine the interve. short term dose-toxicity, and human pharmacokinetics single arm, nonrandomized multiple dose levels less than one year 25-100
Harvard Center for Cancer Prevention - Percentage of cancer deaths attributed to certain factors (top 3)
tobacco use (30%), diet (30%), sedentary lifestyle (5%), another study, infection at 10%
US Can cancer be prevented?
tobacco use, poor nutrition physical inactivity, infectious agents (HBV, HIV, HPV), protecting skin from intense sun exposure, regular screening examination
Cancer causes that are preventable in US
tobacco, diet nutrition, infections (vaccines) -make up greater than half of the causes of cancer
HBV vaccine and Liver cancer
too early to evaluate the benefit of HBV vaccine in reducing liver cancer rates, but studies show that true among children in Taiwan.
US Five-year relative cancer survival rates by race
whites higher than blacks for all cancer sites (70% total vs 62% total)