Environmental Risks

Question 1

What is risk?

Answer 1

The chance or probability that injury or harm will occur

Question 2

What is a risk factor

Answer 2

Characteristic associated with cancer prevelance

Question 3

How can you determine if a characteristic is a risk factor

Answer 3

Determine the relative risk associated with a particular characteristic

Question 4

How is relative risk risk calculated

Answer 4

RR = absolute risk WITH factor/absolute WITHOUT factor

Question 5

What is absolute risk

Answer 5

The chance of getting cancer for a group of individuals
ex - 13% of intact 10 year old female dogs develop mammary cancer

Question 6

If RR is >1, then there is…………….risk

Answer 6

Increased

Question 7

If RR is <1, then there is………………risk

Answer 7

Decreased

Question 8

What are the study types for dtermining RR

Answer 8

Prospective (cohort) study
Retrospective (case) study

Question 9

What is a prospective study

Answer 9

2 populations: 1 exposed to risk factor, 1 not
Monitor for disease
Calculate RR for each population

Question 10

What is a retrospective study

Answer 10

Done ‘after the fact’ eg when patient presents with a disease
Determine which proportion of the population was exposed vs not
Determine odd ratio, determine RR

Question 11

What does RR NOT tell us

Answer 11

The prevalence or incidence
Absolute risk

Question 12

What are some examples of true carcinogenic risk factors

Answer 12

Tobacco
Alcohol consumption
UV radiation

Question 13

How can risk factors be evaluated

Answer 13

Strength of the evidence
Size of associated risk
Impact of risk factor

Question 14

Criteria for evaluating the strength if evidence

Answer 14

Design and execution of studies
Multiple independent studies done?
Dose-response relationship
Plausible biological reason

Question 15

How is the impact of a risk factor evaluated

Answer 15

Size of the RR
How many individuals have the risk factor

Question 16

What are some limitations of risk factor studies

Answer 16

Results only applicable to similar groups
Values are from a low/high comparison and don’t represent the ‘middle’ of the group
Findings apply to GROUPS not individuals

Question 17

What are some ways to use risk factor studies

Answer 17

Screening tools
Risk reduction strategies
Stepping stones for further studies

Question 18

What are some general risk factors for veterinary patients

Answer 18

Age
Physical features
Hormones
Environment
Hereditary factors

Question 19

Lightly colored skin is associated with an increased risk for…

Answer 19

Squamous cell carcinoma

Question 20

Grey horses have a higher risk for…

Answer 20

Melanoma

Question 21

In cattle, what virus increases their risk for what cancer

Answer 21

Bovine leukemia virus –> lymphoma

Question 22

What increases a dog’s risk of mammary cancer

Answer 22

Being spayed after 2nd estrus

Question 23

What increases a dog’s risk for bone cancer

Answer 23

Weighing more than 44kg

Question 24

What increases a cat’s risk of mammary cancer

Answer 24

Being spayed after 6 months of age

Question 25

What increases a cat’s risk of lymphoma

Answer 25

Having FeLV, FIV
Exposed to tobacco smoke

Question 26

What’s the deal with neutering and cancer

Answer 26

Neutered dogs have a decreased risk of dying from infection, trauma, and vascular disease
They have an increased risk of dying from neoplasia and immune-mediated diseases
But, they also live longer and age is a risk factor for cancer