Skin cancer Flashcards
What is the most common skin cancer?
basal cell carcinoma
What is incidence?
the number of new cases of a disease as a percentage of the population who develop the disease over a fixed period
What is prevalence?
the total number of cases at a time in the population
What is xeroderma pigmentosum?
- photosensitivity due to defect in excision repair genes
- predisposition to cancer
- present in infancy with acute reaction to sun
What causes albinism?
defect of tyrosinase
What is Gorlin’s disease?
familial disease that causes many BCCs
What is the main risk with immunosuppression and the skin?
SCC eg IBD, organ transplant etc
What is an oncogene?
operative form of a healthy gene that positively regulates cell division
What are the main skin cancer risk factors?
- UV RADIATION
- genetics
- age
- chemical exposure
- immune suppression
Where do SCCs tend to be?
head, neck, hands and forearms which are typically sun exposed sites
Where do BBC and melanoma tend to be?
less exposed sites (associated with intermittent burning episodes)
What is the biggest risk factor for skin cancer?
sun burn
sun beds and sun burn as a child
What does UVA do?
more common and causes indirect DNA damage with a C to A point mutation
What does UVB do?
direct DNA damage with a CC to TT mutation
in the UK only when the sun is directly overhead
What effect does chronic UV exposure have?
immunosuppressive
