Skin Pathology

Question 1

What is the epidermis made of?

Answer 1

Mainly made of keratinocytes. Has 4 layers - stratum basale/basal is deepest layer, stratum spinosum/spinous layer (thickest layer), stratum granulosum/granulosa layer and stratum corneum/corneal layer

Question 2

Where are melanocytes normally seen?

Answer 2

Stratum basale, interspersed between keratinocytes.

Question 3

What is the base of the dermis?

Answer 3

Collagen

Question 4

Inflammatory reaction patterns in the epirdermis

Answer 4

Spongiotic, lichenoid, psoriasiform, vesiculobullous

Question 5

Inflammatory reaction patterns in the dermis

Answer 5

Vasculitic, granulomatous

Question 6

Inflammatory reaction patterns in the dermis

Answer 6

Panniculitis e.g. erythema nodosum

Question 7

Spongiotic reaction example

Answer 7

Eczema (contact dermatitis,

Question 8

What is seen in eczema

Answer 8

spongiosis edema, superficial …

Question 9

What is seen in lichenoid inflammation?

Answer 9

Lichen planus. Shiny, purple, flat topped scaly papules …

Question 10

Lichen planus is an example of which type of reaction pattern?

Answer 10

Lichenoid

Question 11

Erythema multiforme

Answer 11

Toxic epidermal necrolysis, Steven-Johnsons Synrome

Question 12

What type of reaction pattern is erythema multiforme?

Answer 12

Lichenoid

Question 13

What type of reaction pattern is psoriasis?

Answer 13

Psoriasiform

Question 14

How long keratinocytes?

Answer 14

1 - 28 days to reach the the top

Question 15

How long keratinocytes lives in psoriasis

Answer 15

1 - 7 days, can see nucleus in the cells at the top

Question 16

What happens in psoriasis?

Answer 16

Abnormally rapid turnover of the epidermis results in the accumulation of a thick scale over sites of frequent . Sometimes white blood cells are seen in the corneal layer?

Question 17

Silvery plaque

Answer 17

psoriasis

Question 18

Vesiculobullous reaction pattern examples

Answer 18

Bullous pemphigoid, pemphigus

Question 19

Bullous pemphigoid

Answer 19

large tense bullae …

Question 20

What happens in bullous pemphigoid

Answer 20

Antiboidies attack basement membrane and epidermis lifts of dermis resulting in a blister. Lots of eosinophil, itchy.

Question 21

How to detect bullous pemphigoid

Answer 21

Direct immunofluorescence - linear IgG

Question 22

Pemphigus superficial and deep

Answer 22

Superficial - pemphigus follaceous, deep - pemphigus vulgaris

Question 23

What happens in pemphigus vulgaris

Answer 23

Deep intraepidermal/suprabasal acatholysis

Question 24

Detecting pemphigus …

Answer 24

Intercellular deposits of IgG - chicken wire pattern

Question 25

Where in the epidermis does the bullae in pemphigus vugaris form?

Answer 25

Intraepidermal / stratum spinosum?

Question 26

Primary skin cancers

Answer 26

melanomas, non melanoma (basal and squamous cell carcinoma)

Question 27

What is seborrheic keratosis

Answer 27

Acanthosis, horn pseudocysts ///

Question 28

commonest form of skin cancer

Answer 28

basal cell carcinoma (rodent ulcer)

Question 29

What does BCC look like

Answer 29

Pearly, locally aggressive, hardly ever metastasise, PTCH mutation

Question 30

What is PTCH mutation

Answer 30

Symmetric mutation, caused by UV damage

Question 31

BCC???

Answer 31

Basaloid, peripheral palisading, clefting ...

Question 32

Premalignant condition ... dysplasia in epidermis

Answer 32

...

Question 33

What do you see in dysplasia

Answer 33

atypia of basal layer

Question 34

Bowen's disease (SCC in situ) layers affected

Answer 34

Full thickness atypia, basement membrane intact, increased mitotic activity

Question 35

SCC presentation

Answer 35

Irregular aggregates of pink cells, ..., keratin pearls, perineural invasion, increased mitotic activity

Question 36

Benign naevi - junctional nevus

Answer 36

epidermis

Question 37

Benign naevi - Compund naevus

Answer 37

epidermis and dermis

Question 38

Benign naevi - Intradermal naevus

Answer 38

dermis

Question 39

How do benign naevi look?

Answer 39

Symmetrical, maturation with death (bigger cells at the epidermis junction, gets smaller as it moves down).

Question 40

Malignant melanoma A - G

Answer 40

Asymmetry, border, colour variation/change, different/diameter, e...

Question 41

malignant melanoma what does it look like?

Answer 41

cellular atypia, asymmetry, pagetoid spread (ascend in the epidermis)

Question 42

stains for malenocytes

Answer 42

....

Question 43

Melanoma prognistic indicators

Answer 43

*Breslow thickness, *ulceration, lymphovascular invasion, perineural invasion, Clark level, microsatellites, TILs, regression, mitotic index