CNSLF Surgery - Skin Cancers (i)
Intro
all are increasing in incidence esp among Caucasians (due to increasing age + sun exposure)
main skin cancers are...
BCC (most common)
SCC (can be more aggressive)
malignant melanoma (MM)
Uncommon skin tumours
angiosarc
atypical fibroxanthoma
Merkel cell carc
v aggressive
elderly
mets quick
high mortality
cut B or T cell lymphoma
extramammary Paget's disease
Kaposi sarc (a/w HIV)
penile intraepithelial neoplasia
vulvarintraepithelial neoplasia
cut mets: breast, RCC
Risk factors
fair skin
sunlight/UV exposure (through clouds, sunbeds) = by far the biggest
immunosuppression (e.g. transplants) = possibly viral
radiation
chemical carcinogens (hydrocarbons)
inherited disorders (Albinism - no protection)
chronic irritation
Marjolin's ulcer = rare aggressive SCC arising from previously traumatised tissue
large no of naevi
50% of MMs arise in existing pigmented lesions
could be familial
pre-malignant conditions (e.g. Bowen's disease = v early form of SCC)
Pre-malignant conditions
actinic keratosis
aka solar or senile keratosis
red scaly patch on exposed skin
unstable cells due to sun damage - produce too much keratin
common in elderly + Causasians
excision = most effective tx
lesions are removed when they ulcerate or bleed
bowen's disease
carc in situ
similar to actinic keratosis
rough reddened patch of skin
should be excised because of risk of malignancy
cornu cutaneum
majority are benign but may be pre-malignant
cortical projection above level of skin
increased keratin
malignancy may be found @ base, most commonly SCC
BCC
high risk
head + neck
diameter > 20mm
poorly defined margins
arises from basal cells in epidermis
rare met
can invade bone + cart
clinical small nodules - ulcerate - raised 'pearl' edges
predilection sites: 90% on forehead, face or hair margin (normally hair protects scalp unless thinning)
can be fatal if left long enough (can erode through bone + cart)
should bx
types
nodular
pearl-like sheen
slow growing
cystic
nodulo-cystic (mix)
ulcerative
tumour has outgrown its blood supply
could be infiltrating (tends to grow down with unclear margins
superficial
pigmented
morphoeic
tx
shave (might not get base), cautery, curettage
photodynamic tx (tumour absorbs photosensitising drug, then destroyed by light)
imiquimod (immune response modifier - 5% Aldara)
cryotx
radiotx
Moh surgery
check under microscope if adequate resection
minimises tissue needed to be excised
surgical excision - usually with local anaesthetic
telangiectasia (visible vessels)
SCC
high risk
lip - worse prognosis s invades muscle quicker + has access to lymphatics
diameter > 20mm
site of chronic inflamm process
malignant tumour arising from keratinocytes of epidermis
destructive
mets mainly via lymphatics (2-6%)
cut or head+neck - not skin, not like mucosal SCC (more aggressive
met potential based on...
site (e.g. lip a/w lymphatic spread)
size > 2cm
depth > 4 mm
histology (poorly differentiated)
host immunity
perineurial/perivasc spread (tender/hot)
fixed (worse than mobile)
management options
surgical excision
primary site vs regional control
if you take down to bone you can't perform a skin graft
radiotherapy - primary site vs regional control