Skin Cancer Flashcards
What is a basal cell carcinoma
A non-melanoma skin cancer arising from keratinocytes in the epidermis
Sun exposure pattern commonly causing BCC
intermittent, intense sunburn episodes
Most common skin cancer
BCC
Presentation of BCC
painless slow growing lump or non-healing ulcer
“stuck on” appearnace
pearly border
central ulceration - rodent ulcer
telangiectasia - visible, aborising blood vessels
Types of BCC
nodular
superficial
infiltrative
Spread of BCC
no mets
Tx of BCC
surgical excision
What is a squamous cell carcinoma
Non-melanoma skin cancer arising from keratinocytes in the epidermis
Sun exposure pattern of SCC
chronic, cumulative UV exposure
Precursor lesions of SCC
- Actinic keratoses
- epidermal dysplasia - Bowens disease
- slow growing red, scaly plaque
- squamous dysplasia
Presentation of SCC
hyperkeratotic (crusted) lump or ulcer
relatively fast growing
What is a cutaneous horn
compact keratin that has grown
ear, lip and scalp are high risk sites
can be a SCC
Tx of SCC
Surgical excision -
4mm margins if diameter <20mm
6 mm margins if diameter >20mm
Mohs surgery -
high risk patient or cosmetically important site
What is a malignant melanoma
Tumour arising from the melanocytes in the basal layer of the epidermis
Signs that would make you suspect melanoma
change in shape
irregular pigmentation
bleeding
development of satellite nodules (tumour nodules appearing > 0.5mm from the primary lesion)
ulceration
new pigmented lesion developing in adulthood
4 main types of melanoma
- superficial spreading
- acral/mucosal lentiginous
- lentigo maligna
- nodular
What is radial growth phase (RGP) of malignant melanoma
tumour grows as macule/patch - everything is above the epidermal basement membrane - so there are no vessels for the melanoma to get into and spread
What is vertical growth phase (VGP) of malignant melanoma
Invasion of melanoma cells vertically into dermis, forming an expansile mass. Tumour has metastatic potential.
What types of melanoma have a RGP
Acral/mucosal lentiginous
Lentigo maligna
Superficial spreading
What types of melanoma only have a VGP
Nodular melanoma
How is prognosis of melanoma determined
Tumour depth - Breslow thickness
< 1mm depth: 95-100% 5 year survival
> 4mm depth: 50% 5 year survival
Metastases: 5% 5 year survival
‘ugly duckling sign’
all moles are light brown except one - sign of malignant melanoma
Ix for suspected malignant melanoma
simple dermatoscopy, then
skin biopsy
+/- sentinal node biopsy if suspicion of metastatic disease
ABCDE rule for moles
Asymmetry Border Colour Diameter Evolution
Tx of melanoma
- surgical excision
- Imiquimod (aldara cream)
+/- sentinel node biopsy from Stage 1 onwards
Most common presentation of Bowen’s disease
Elderly female
Lower legs most common area
Tx of Bowen’s disease
Topical 5 fluoro-uriacil (Efudix)
or
Imiquimod (Aldara)
What is a Marjolin Ulcer
aggressive SCC that occurs at the site of ulceration or trauam
Risk factors for developing SCC
Immunocompromisation - e.g. transplant patients, HIV
excessive exposure to sunlight / psoralen UVA therapy
actinic keratoses and Bowen’s disease
smoking
