Flashcards in Principles of Cancer Detection and Management Deck (18)
Screening may involve (4 things)
2 main requirements for a cancer screening test
Preclinical stage of the cancer must be detectable and have a long history
Evidence that early detection improves outcomes through effective treatment
What proportion of the cancers are detected with my test?
True positives/total cases with cancer
The total includes people with cancer who didnt screen positive
What proportion with a negative test DON'T have cancer?
True negative/total negative
Positive predictive value
What proportions of positive cases have cancer?
Positive cases with cancer/total positive cases
Just looking at the people who screen positive
Depends on the prevalence of cancer in the population
3 strategies to make screening worthwhile
Select accurate tests
Test in populations with high prevalence
Dont test in populations with short life expectancy
3 cons of screening
Exposing people to the risk of the further testing and anxiety
Circulating tumor DNA
Shed into the bloodstream by tumors
Potential screening tool
Before treatment, you want to confirm cancer with what?
A tissue diagnosis!
TNM system to stage solid cancers
T: primary tumor characteristics (size and depth)
N: nodal status (involved or not, number, size)
M: metastasis (present or absent, extent)
Why is lymph node involvement significant?
Indicates potential widespread disease despite normal staging investigations
Used to determine the need for additional post-op treatment
Means that the treatment is not being given with curative intent
3 types of treatment for cancer
Damages DNA in tumor and normal cells
But there are better repair mechanisms in normal cells so it differentially kills tumor cells
3 types of systemic therapy
Chemotherapy (kills rapidly dividing cells)
Targeted therapy (disruption of tumor cell proliferation and/or survival factors
Immunotherapy (marking tumor cells for destruction, or removing signals that are suppressing the immune response)
Given after the primary therapy (usually surgery) to maximize effectiveness
Aim is to eradicate undetected microscopic disease
Treatment given prior to the primary therapy (usually surgery)
Shrinks the tumor to allow safe removal