Pigmented Skin Lesions Flashcards
What are melanocytes derived from/where to they go?
neural crest
go from neural crest to skin, ureal tract, leptomeninges
What causes red hair?
phaeomelanin
What causes freckling?
defect in MCIR
What happens if you have two defects in MCIR?
red hair and freckling
What are liver spots?
actinic lentigines (related to UV exposure)
Are Melanocytic naevi congenital or acquired?
can be either
Are malignant melanomas commoner in male or females?
females
What is RGP?
Grow as macules when either entirely in-situ or with dermal microinvasion
What is VGP?
Eventually the melanoma cells invade the dermis forming an expansile mass with mitoses
Can VGP or RGP metastasise?
only VGP
What happens if wild type gene BRAF is mutated?
drives cell proliferation by up-regulating MEK and ERK
Which type of melanomas do not have any significant surrounding macular pigmentation and normally occur in older patients?
nodular
Which melanoma type also affects eldery patients and usually affects palms or soles or nails?
Acral lentiginous melanoma
What is Hutchinson sign and in which type of melanoma is it seen?
pigmented extension into the nail fold
Acral lentiginous melanoma
What does this describe: brown / black greasy lesions often on trunk usually multiple “stuck-on” appearance often “warty” but may be flat regular border
Seborrheic keratoses
