Skin Cancer Flashcards
basal cell carcinoma from… looks like…
germinative kcytes
resemble basal layer
squamous cell CA form, looks like
epidermal kcytes
resembles spinous layer
melaoma from/resembles?
melanocytes
most common mut in sporadic tumors of
PTCH
what places squamous cell CA pt at high risk of met
ear/scalp/nose/lip immsupp arise in scar/ulcer/burn/sinus/genitals arsenic bone mm nn big / deep
px of melanoma most important?
ulcer, dept of dermal inv
nonmelanoma skin cancer risk in US
1/5 lifetime risk
most comon invasive neoplasm in US?
basal cell CA
mut in basal cell
PTCH 30% in sporatic ones
what is PTCH
tsg, regulates basal epidermal cell prolif
risk of basal cell
UV, fair, hx of sunburn, fam hx, immsupp (10x)
upper vs lower face?
basal/ squamous
most common subtype of basal cell
nodular
pathology of basal cell
basophilic hyperchrom cells –> nodules from surface
subtypes of bvasal cell
nodular, sup’l, pigmented, morpheaform (scloeritic), micronodular, cystic, infiltrative
basal cell nevus syndrome (Gorlin)
auto dom, rare mut PITCH 1 (so sonic hedgehog takes over, lots of exp) early age BCC like 23 yo MSK defect, jaw cysts inc risk of medulloblstoma, fibrosarcoma
mets in basal cell
rare
tx basal cell
excise, electroodess+ curretage, cryosurg, radiation, topical chemo if superficial (imiquimod, 5-FU)
Vesmodegib
tx adv basal cell
competitive antagonist
super expensive, only for ptch muts, bad musc cramps, GI distress
squamous cell gross
CRUSTY, hyperkeratotic
development of squamous cell
uv dam –> mut p53 –> epid cells –> squamous cell dysplasia –> squamous cell carc in situ –> breaks through basal layer, invasive
second most common skin CA
squamous cell
progression
minimal atypical (actinic keratosis)
full epid atypia above BM (SCC in situ)
invasive (SCC)
Bowen’s disease
SCC in situ
eryhtroplasia of queyrat
SCC in situ on genitalia
actinic keratoses
thin non indurated lesions lack of induration is clue to tell us it is so superficial not thick you see a bunch of them SUN EXP AREA
ssquamous cell mut?
no specific. often p53 mut
risk of squamous cell
UV, HPV (16, 18, 31, 35) luekoplakia immunosupp chem (arsenic) radiation burn scars chronic inflamm
risk of squamous metastasis
related to size, depth of invasion, anatomic site, host immune status
>2 cm
>4 mm depth
LIPS AND EARS
how many squamous cell met
<5 %
higher risk of squamous mets?
actinic induced on lip
marjolin’s ulcers
HPV induced
leukoplakia
where does squamous cell met?
nodes
lung
if squamous on actinic induced non-mucosal skin, risk of met?
lower. 0.5-1%
keratoacanthoma
neoplasm of kcytes
type of fast growing squamous cell
painful
body elminates it spontaneously
Marjolin’s ulcer
ulcerated invasive squamous cell on inflamm/scar/radiation/truama
squamous tx
depends on progression
actinic – topical, cryo
in situ: topical, intralesional, excision
invasive: excise
