Clinical Correlation Flashcards
What is epidemiology?
The study of distribution, determinants, prevention, and control of disease (i.e. cancer) in human populations
What is descriptive epidemiology and where is it used?
Descriptive epidemiology tells you something, but doesn’t tell you why
It’s used in determining the *distribution* of cancer in human populations (eg. site, stage, pathologic characteristics, race, gender, geography)
What is surveillance?
Part of descriptive epidemiology
The collection, analysis, and interpretation of health data essential to planning, implementation, and evaluation of public health practice and dissemination of these data
What is the most commonly diagnosed cancer in men? In women?
Men: prostate cancer
Women: breast cancer
What is analytic epidemiology and what does it entail?
Describing WHY something occurs, what causes it and/or what prevents it
It entails employing epidemiologic study design, epidemiologic method, biostats, and understanding of cancer biology
What are some overarching risk factors for cancer?
Aging- all but pediatric cancers
Tobacco- mouth, esophagus, stomach, pancreas, larynx, lung, breast, prostate
Alcohol- esophagus, stomach, liver, pancreas, colon, larynx, lung, breast, prostate
Ionizing radiation: x-ray, radiotherapy, radon- thyroid, AML, breast, lung, stomach, colon, esophagus, bladder
UV radiation- skin
Obesity- colon, esophagus, breast, kidney, endometrium
Low physical activity- colon, breast, endometrium
Low fruit/veggie intake- colon, lung, head/neck, esophagus
Occupational exposurses: heavy metals, vinyl chloride, asbestos- lung, liver
Infections- liver (HBV/HCV), skin (HIV, HHV8), lymphoma (HYLV-1/2, EBV), cervix (HPV), stomach (H pylori)
Hormones- endometrium, ovarian, breast
Family history- breast, colon, lung, prostate, hematologic, melanoma
What is molecular epidemiology?
A subdivision of cancer epidemiology, entails the examination of biologic markers (as proxies) of exposure, disease and points in between
What are some examples of exposures that can be measured by molecular epidemiology?
blood cytokines and acute-phase proteins
SNPs
fatty acids in blood
What are some examples of diseases that can be measured by molecular epidemiology?
tumor histology
tumor differentiation
tumor COX-2 expression
PSA test
What are some examples of “points in between” that can be measured by molecular epidemiology?
breast density
DNA adducts
miRNA expression
global DNA methylation
nicotine exposure
What are the advantages of biomarker data? Disadvantages?
Advantages:
- Objective
- Some samples easily obtained (buccal swab, hair, toenails)
- Reduces bias
- Can address “exposures” participants may not know about (eg. Gene expression, w3 level, methylation, polymorphisms)
Disadvantages:
- Often difficult to obtain (eg. Tissue biopsy, blood)
- Limited by lab technique
- Some markers represent very short-term or recent exposures (eg. Aspirin metabolites in urine– need tissue sample for more long-term exposure)
- More tests = more false positives
- Results are not always easily interpreted
What are the features of experimental/clinical science versus observational science?
Clinical: largely experimental, focuses on treatment, low sample size, can examine mulptiple cancers but only 1-2 exposures, exposures are assigned, not as prone to bias, more expensive, not representative of general population, can inform causation
Observational: largely observational, focuses on prevention, large sample sizes, exposures are observed, can examine multiple cancers and multiple exposures, prone to bias, less expensive, more representative of general population, can inform causation
