Cancer Epidemiology Flashcards
what are leading causes of death globally?
Ischaemic heart disease and stroke
what are the changes in death rate in CVS and cancer over the years?
o Death rates from CVS disease have dropped over the years.
o Death rates from cancer have remained stable/increased-slightly over the years.
what are the most common cancers among men?
prostate and lung cancers
what are the most common cancers among women?
breast and cervix uteri cancers
examples of cancer incidence differing dependent on geographical location
Melanoma is most common in AUS/NZ and colorectal cancer is most common in Japan.
how are migrant studies useful
the rate of change following migration can indicate to what level a cancer is genetic or environmentally influenced
what does rapid change in cancer incidence after migration indicate?
environmental factors and lifestyle act late in carcinogenesis
what does a slow change in cancer incidence after migration indicate?
exposures early in life are more relevant i.e. genetic
what does persistence in rates in cancer incidence indicate?
genetic susceptibility is important in determining risk.
why may cancer incidence be increasing in both high and low income countries?
effects of earlier diagnosis, screening and changes in risk factors.
the introductions of official screening procedures
what is the effect on the incidence of cancer in high income countries after the introduction of screening programmes?
High income countries tend to show an increasing and then rapid increase followed by a plateau of cancer incidence
how is mortality changing in high and low income countries?
decreasing in HI countries
not decreasing in LI countries as the total burden of cancer increases
what percentage of cancers are of hereditary inclination?
5-10% of cases
what are the attributable risks of cancers in order of highest to lowest?
Smoking diet infection reproductive hormone alcohol occupation
how much of an impact do modifiable risks have on the cancer burden?
o 45% (men) and 40% (women) of cancers could have been prevented by reducing risk.
Smoking – 30% of cancer death, increases risk for >15 cancers, 90% (men) and 80% (women) of lung cancer causes.
what modifiable risk factor increases chances of colorectal cancer?
diet:
risk increases with a low fibre diet
what cancers are associated with alcohol?
liver oral cavity pharynx larynx oesophageal cancer
even though it has a CHD preventative effect
what are the dietary prevention guidelines for cancer prevention?
o Be lean without being underweight.
o Be physically active for at least 30 minutes a day.
o Avoid sugary drinks.
o Eat a variety of fruit/veg.
o Limit consumption of red meat (<500g/week) and avoid processed meat.
o Limit alcoholic drinks.
o Limit consumption of salty foods.
what do increased sex steroids increase the risk of?
breast cancer
what are some causes of cancer of viral origin?
HPV (cervix cancer)
EBV (Hodgkin’s/Burkett’s Lymphoma),
HCV/HBV (liver cancer)
H. pylori (stomach cancer).
what are the 5 major cancers contributing to worldwide mortality?
lung stomach liver colorectal breast
lung has seen little therapeutic progress
describe the current prevalence and incidence of cancer
There are approximately 14 million new cases of cancer every year
these diseases kill approximately 8 million people worldwide every year.
Approximately 33 million people worldwide are living with cancer (within 5 years of diagnosis).
It is estimated that there will be at least 16 million new cases per year by 2020, and the number of new cases is expected to rise by 70% over the next 20 years.
Cases per year
Deaths per year
Living (within 5 years of diagnosis)
- 14 milllion
- 8 million
- 33 million
what is the reason for increasing cancer prevalence?
increasing life span and unhealthy lifestyles
which cancers are common in young boys?
lymphomas
common cancer types in children (0-14)
- Leukaemia
- Brain/CNS tumours (claim the most lives)
- lymphomas
cancers are a leading cause of death of children
what are common cancer of children under 5?
- embryonal solid tumours such as neuroblastoma, retinoblastoma and Wilms’ tumour
- acute lymphoblastic leukaemia (ALL)
what are the causes of avoidable death due to childhood cancer?
- lack of diagnosis
- misdiagnosis or delayed diagnosis
- obstacles to accessing care
- abandonment of treatment
- death from toxicity
- higher rates of relapse.
