Benign and Malignant Melanocytic Lesions Flashcards
- all types of benign lesions arising from epidermis (5)five in objectives. six others
- full overview is at beginning of other deck on lesions
-viral warts
-cutaneous horn
-seborrhoeic keratosis/wart
- skin tag
- linear epidermal naevus
-mealnocytic naevus
-sebacous naevus
-epidermal/pilar cyst
- milium
- chrondrodermatitis nodular helicis
-keratoacanthomatous scc benign scc
- naevus. define (1). histologically cells resemble what cells (1). may be composed of (4)
- main 3 types and what they are composed of
-naevus = a skin lesion that has localised excess of one or more types of cell in a normal cell site. histologically cells resemble normal cells.
-may be composed
>keratinocytes
>melanocytes
>connective tissue
>mixture of epidermal and connective tissue
-linear epidermal naevi - composed of keratinocytles
-melanocytic naevi - composed of melanocytes
-sebaceous naevi - composed of mixture of epidermal and connective tissue
-melanocytic naevi. aka(1) are localised benign tumours of melanocytes.
- cause (2)
- four main types (4)
- there are four other types (4)
- aka moles.
- cause unknown. genetic and sun exposure thought to be factors.
- four main types are junctional, compound and intradermal these three are based on location of cells within the epidermis. and congenital
- spitz naevi, blue naevi, mongolian spots, atypical naevus syndrome
-benign melanocytic naevi
- congenital. present when (1) usual size (1) colours (3). with maturation some become protuberant and hairy, can be disfiguring. carry an increased risk of (1)
- junctional. shape (1) type of lesion (1) colour (2). naevi in which areas tend to be these (4)
-congenital. present at birth. usual size less than 1cm. can be black, brown, blue. with maturation some become protuberant and hairy, can be disfiguring. carry an increased risk of malignanct transformation
-junctional. roughly circular. macules. brown or black (may vary within). most melanocytic naevi of the palms, soles, mucous membranes, genitals are this type.
benign melanocytic naevi
-compound. shape (1). type (1). size (1) colour (1) may bear what (1)
-intradermal - look compound but with what difference (1)
-compound - dome shaped. nodules. up to 1cm diameter. brown. may bear hairs.
-intradermal - less pigmented, often skin coloured
-spitz naevi. seen most often in who (1). growth?(1) colour (2). type (1)
-blue naevi. - just a blue naevi
-mongolian spots - seen in who (3) usually fade, look like (1)
-atypical naevus syndrome - atypical melanocytic naevi.
>can run in families or occur sporadicaly.
>irregular pigment and border and sizes. many larger than 1cm.
>some may be malanoma prone.
> pts with this syndrome and a positive FH of malignant melanoma should be followed up 6 monthly for life.
-spitz. children. rapid growth. red or pink. nodules.
-mongolian spots - seen in who most downs babies, many asian and black babies. greyish bruises.
- benign naevi may undergo malignant change - to melanomas. may occur in what naevi (2)
- excision required when (3)
-congenital naevi and atypical naevus syndrome rare in other naevi
-unsightly, malignancy expected or known risk, naevus repeatedly inflammed or traumatised
- all types of malignant lesions of the epidermis (4)
- all type of premalignant lesion (2)
nb not just melaocytic
- basal cell carcinoma
- squamous cell carcinoma
-malignant melanoma focus of this deck
- pagets disease of the nipple strictly a breat tumour
- -*actinic keratoses - premalignant lesion that occur on sun damaged skin. they are called premalignant as they are technically squamous cell carcinomas in situ but they rarely invade/progress to scc
- -*bowens -same as above but slightly more likely to invade/progress to scc
-sx and signs of melanoma in history (3) abcde (7)
- itch, pain/burning, bleeding
- a - (a)symmetry, shape - ASYMMETRY
- b - borders/margins - IRREGULAR
- c - colour - VARIABILITY may be tan, brown, pink, black, blue
- d - diameter - OVER 0.5 CM DIAMETER
- e - evolving, extra surface characteristics - such as inflammation, ulceration
-risk factors (3)
-genetic
> susceptability genes
>susceptible phenotypes - pale skin, blond or red hair, freckles, burn
-sunlight
-prexisting melanocytic naevi
>congenitcal naevi
> atypical naevi syndrome
malig melanoma - growth phases (3)
1) macule. irregularly pigmented and asymmetrical.
intra-epidermal/in situ change
2) plaque. radial growth. may be palpable.
intraepidermal/in situ change
3) nodule within plaque. radial and verticle growth. eaily palpable. invasive..
verticle growth invading dermis
-four main types of malig melanoma
- lentigo maligna melanoma
- superficial spreading melanoma
- acral lentiginous melanoma
- nodular melanoma
-lentigo maligna melanoma occurs where? in which sort of people? . features (2) course?
-superficial spreading melanoma. most common type in caucasions. radial growth phase shows varied (1) . what signifies invasive phase
-lentigo occurs on exposed areas in the elderly. irregularly pigmented and shape. may have been an enlarging macule for many years as in situ melanoma before invasive nodule appears.
superficial spreading. radial growth phase shows various colours. often palpabe. a nodule coming up within a plaque signifies dermal invasion and poor prognosis.
-acral lentiginous melanoma. occurs where (2). rare in which phenotypes. (1) common in which (2). what signifies invasive phase
-nodular melanoma lacks what growth phases. prognosis
-acral lentiginous soles and palms, rare in caucasoids. more common in chinese and japanese . nodule coming up in plaque signifies dermal invasion
-nodular. lacks in situ growth phases. most poor prognosis
benign melanocytic naevi- differentials (5)
maignant melanoma - differentials (7)
benign melanocytic lesions - differentials
-malignant melanomas most important differential
-seborrhoeic keratoses
- lentigines may be found on any part of skin or mucous membranes. more profuse than junction naevi. may develop in adulthood.
- hemangiomas benign proliferations of blood vessels- located in dermis , not epidermis
- ephelides freckles
malignant melanomas - differentials
- benign melanocytic naevi
- seborrhoiec keratosis
- -*lentigines
-hemangiomas sclerosing
- -*actinic keratosis a pigmented one
- -*basal cell carcinoma a pigmented one
- -*hematoma
-prognosis and staging
