Skin cancers 1 Flashcards
What is cancer?
a term for diseases in which abnormal cells divide without control and can invade and colonize nearby tissues
What is a tumour?
An abnormal mass of tissue
Hallmarks of cancer?
Resists cell death, genome instability, sustaining proliferation,
WHat is carcinoma?
a cancer that begins in an epithelium
What is a sarcoma?
A cancer that begins in the connective tissue or supportive tissues
What are some tissues that a sarcoma could begin in?
bone, cartilage, fat, muscle, blood vessels
Diff types of skin cancers?
Keratinocyte cancers, melanoma
Diff types of keratinocyte cancers?
Basal cell carcinoma (BCC), Cutaneous squamous cell carcinomas (cSCC)
Keratinocyte cancer proportions?
BCC–> 80%
cSCC–> 20%
Skin cancer proportions?
Keratinocyte–> 99%
Melanoma–> 1%
Where do keratinocytes originate from?
Epidermal stem cells
What is the most lethal type of skin cancer?
Melanomas
Why are melanomas the most lethal type of skin cancer?
They are able to undergo metastasis and spread to other parts of the body
Rare skin cancers?
Merkel cell carcinoma
Skin adnexal carcinomas
Kaposi’s Sarcoma
Cutaneous T-cell lymphoma (CTCL)
Most common cancers in the world?
Skin cancers
Cases per year of non-melanoma vs melanoma?
156,000 non mel
16,700 mel
Deaths per year of non-melanoma vs melanoma?
918 non mel
2341 mel
Age group of non-melanoma vs melanoma?
90+ non mel
85-89 mel
Why is melanoma one of the most common cancers in young adults?
Sunbeds and sunbathing
WHat can UV radiation be divided into?
UV-C, UV-B, UV-A
What is UV-C blocked by?
mesosphere
What is UV-B and A blocked out by?
Ozone layer and stratosphere, but a lot of B and A still reaches the surface
Wavelengths of diff types of UV?
C–> 100-280nm
B–> 280-315nm
A–> 315-400nm
What does it mean for a UV radiations energy if it has a shorter wavelength?
Higher energy
Where does UVB penetrate?
Only into the epidermis
What does UVB cause?
DNA damage to the keratinocytes in the epidermis, massive cell death
Where does UVA penetrate?
Deeply into the skin–> into the dermis
What is UVA associated w/?
Skin aging
What does UVA cause the production of in the dermis?
Oxygen radicals
