Week 3 Flashcards
What are the two types of non-melanoma skin cancer? From what cell type do they originate?
Basal cell carcinomas
Squamous cell carcinomas
Both arise from keratinocytes
Describe the epidemiology of melanoma - what % of skin cancers does it make up, who gets it most etc.
Makes up 5% of all skin cancers, but accounts for 75% of all skin cancer deaths
Most common form of cancer in 15-24 year olds
Twice as many women get it, but more men die with it
Fastest increasing cancer in Scotland, rates have been rising significantly
What measurement system is used to grade melanoma depth? How is 5 year survival affected?
Breslow Thickness
< 1mm = 5 year survival of 95-100%
> 4mm = 50%
If metastatic = 5%
What is the ABCDE approach used to diagnose melanoma early?
A - asymmetry
B - border
C - colour
D - diameter
E - evolution
What is the “ugly duckling” sign? How does it reflect the growth of melanomas?
Where one lesion in particular stands out
Melanomas start off superficial and grow out, before the start growing down through the epidermis. This process can occur very rapidly
Give a brief description of basal cell carcinomas
75% of non-melanoma skin cancers, and are very common
Appears as a slow-growing lump or non-healing ulcer
Painless, often ignored
Pearlescent in colour
May have central ulceration, described as a “rodent ulcer”
Locally invasive but rarely metastasise
Appear in the over 40s typically, but can appear earlier
Can have various presentations - nodular/nodulo-cystic, superficial, morphoeic, pigmented etc.
Give a brief description of squamous cell carcinomas, Where do they arise particularly?
Remaining 25% of non-melanoma skin cancers and account for more deaths than BCCs. About 20% of all cancers
Appears as a hyperkeratotic crusted lump/ulcer - “cutaneous horn” sign
Arises on sun-damaged skin
Grow relatively fast, may be painful/bleed
The majority are well-differentiated and low risk, although some are poorly differentiated and high risk. Risk of metastasis is about 5%, and becomes incurable
What precancerous skin lesions are highly suggestive of the development of BCCs or SCCs?
Actinic Keratoses
