Epidemiology of Cancer

Question 1

What is cancer incidence related to, which is the least significant (4)

Answer 1

 Age
 Common environmental causes
 Genetics (although this is a minor relation compared environmental exposures, only 5-10% of cancers)
 Geographical variation and secular trends

Question 2

What are 3 risk factors for cancer

Answer 2

Smoking, diet, alcohol

Question 3

Are familial/inherited cancers rare or common

Answer 3

Rare

Question 4

What do the levels of disease in a population not changing over time suggest as to the cause

Answer 4

Genetic causes rather than environmental exposures

Question 5

Which types of cancers have an increasing incidence

Answer 5

Lung and stomach

Question 6

Regarding all cancers, are they increasing/decreasing/plateauing etc

Answer 6

All cancers were increasing but now are plateauing

Question 7

Why are mortality of cancers decreasing in most places? Give an example of where this is not the case and why

Answer 7

Due to earlier diagnosis, screening and treatment. Not in Africa due to difficulties in getting early diagnosis and little access to diagnostic devices

Question 8

What lowers the risk of colorectal cancer

Answer 8

High fibre diet

Question 9

What % of cancers are due to infectious agents and where is this more common

Answer 9

16% and more common in low income countries

Question 10

Is cancer mortality increasing or decreasing and where and where

Answer 10

Decreasing in most high income countries but not low income countries

Question 11

Why is the total burden of cancer increasing

Answer 11

Because of demographic changes (ageing population., increasing size) and Westernization of lifestyles