Skin Cancer Flashcards
what are malignant skin cancers?
melanoma, basal cell carcinoma, squamous cell carcinoma
epi of melanoma
most dangerous skin cancer, presenting more frequently in young
pathology of melanoma
mutation in serine protein kinase B-RAF (V600E gene), RAS or MAPK pathways
why are melanomas so dangerous?
melanocytes are motile so ca spread more easily
aetiology of melanoma
sun- intermittent exposure, exposure to UV, genetic predisposition
risk factors for melanoma
pale skin, >50 melanocytes naevi, sun sensitivity, atypical mole syndrome
what are some skin conditions that are risks for melanoma?
lentigo maligna: slow growing, macular area of pigmentation on elderly due to sun damage (face)
xeroderma pigmentosa: super photosensitive due to defective NER (nucleotide excision repair proteins)
albinism: no melanin
recessive dystrophic epidermolysis bullosa: type VII collagen deficiency
what are the types of melanomas?
. lentigo malignant melanoma- sun damage
. superficial spreading malignant melanoma- large, flat, irregular that grows laterally. trunk and limbs
. nodular malignant melanoma- most aggressive, rapidly growing pigmented nodule which bleeds
. acral lentiginous melanoma- palm or sole lesion
. familial melanoma- mutations to genes
VGP means…
local invasion of melanoma
what gene mutations cause familial melanoma
mutations to CDKN2A and CDK4
dx of melanoma
ugly duckling signs, dermatoscope Asymmetry Border Colour Diameter (>6mm) Evolution characteristics
red flags for melanoma?
bleeding, ulceration, de novo, nodule
what is mx for melanoma
surgery is only curative option, preventative (sun cream etc)
T/F: <1mm melanoma lead 3cm margin
F: <1mm= 1cm margin
>2mm= 3cm margin
metastatic mx of melanoma
remove regional LNs (if sentinel biopsy +ve), radio/chemo, biologics (MAP kinase inhibitor etc)
prognosis of melanoma/scoring systems
clark's level: depth if invasion Breslow's thickness - pTis= in situ so 100% survival - PT1= <1mm - pT2= 1-2mm - pT3= 2-4mm - pT4= >4mm (20% survival)
where do melanomas usually spread to
skin, heart, lungs, GI, liver, brain
if melanoma spread to lungs, what is this called
pulmonary metastatic melanoma
what is basal cell carcinoma
non-melanoma malignant skin cancer (not melanocytes that are defective)
T/F: basal cell carcinoma (BCC) is the most common type of skin cancer
T
pathophysiology of BCC
basal cell in epidermis invade dermis
aetiology of BCC
intermittent burning episodes, mutations to PTTCH1 genes, Gorlin’s syndrome
triad for Gorlin’s syndrome?
early onset, jaw cysts, palmar pits
types of BCC?
nodular superficial pigmented morphoeic basosquamous
s/s of BCC
slow growing, non-healing ulcer/lump, painless, locally invasive
sites- face, neck
what does a BCC lesion look like
pearly/ translucent/ shiny, telangiectasia, central ulceration, can be pigmented
mx for BCC?
wide excision
surgery for morphoeic BCC?
Mohs Micrographic surgery
epi of squamous cell carcinoma (SCC)?
least common but grows faster
aetiology of SCC?
sun damage or chronic cumulative UV exposure, acitinic keratosis (rough scaly erythematous patches and surrounding skin with lentigines), Bowen’s disease, HPV, trauma e.g. burn sites
what is Bowen’s disease?
indolent form of SCC in situ, slowly enlarging red patch with irregular border and no dermal invasion
lesion for of SCC?
warty/crusted painful nodule, may ulcerate, ill defined
common SCC sites
earl, lip, scalp
mx for SCC?
surgical excision + radio
what are some benign skin lesions?
seborrheic keratosis, melanocytes naevi, dermatofibroma, dermatofibrosarcoma protrubens, angioma etc
what is seborrheic keratosis
common harmless wart growth
pathophysiology of seborrheic keratosis
overgrowth of basal keratinocytes
histology of seborrheic keratosis
epidermal acathosis, hyperkeratosis, horn cysts
s/s of seborrheic keratosis
flesh coloured to very dark brown, greasy stuck on appearance, rough warty surface
sites of seborrheic keratosis
face, trunk, greasy hyperkeratotic surfaces
mx of SK
removal via curettage, cryotherapy, electrodessication
what are melanocytic naevi
benign proliferations of overgrowth of melanocytes
epi of naevi?
congenital- at birth acquired - children= junctional naevus - adolescents= compound - adults= dermal
types of naevi
dysplastic= >6mm, border asymmetry, sporadic or familial
halo naevi= peripheral halo of depigmentation due to lymphocytes
blue naevi= blue/gray due to pigment rich dendritic spindle cells, entirely dermal
spitz naevi= <20yo, consists of spindle or epithelial cells
pathophysiology of naevi
keratinocyte ratio breaks down at cutaneous sites
- junctional: proliferation fo melanocytes at DEJ
- compound: proliferation of melanocytes into dermis
s/s of naevi
even pigmentation and regular borders- larger lesions have inc risk of melanoma
what is dermatofibroma
pink/beige firm nodule, may follow trauma/ bite, F legs
what is dermatosarcoma protrubens
starts as bruise/ scar and as it grows lumps of tissue form
what is an angioma
derived from cells of vascular/ lymphatic system, tiny red papules found on trunk
fast growing painless flesh coloured/ bluish red nodule on sun-exposed sites is…
Merkel Cell Carcinoma
t-cell lymphoma that causes lymphoproliferation is called….
mycosis fungoides
s/s of mycosis fungoides
itchy scaly patches which start on buttock (asymmetric)
ix and tx for mycosis fungoides
ix- biopsy shows invasion of epidermis by T-cells
tx- relapse/chronic course
