Skin tumours and Inflammtory disease

Question 1

What are the clinical three stages of dermatitis?

Answer 1

Acute dermatitis - skin red, weeping serous exudate +/- small vesicles.

Subacute dermatitis - skin is red, less exudate, itching ++, crusting.

Chronic dermatitis - skin thick and leathery secondary to scratching.

Question 2

What is spongiosis? seen microscopically in dermatitis

Answer 2

intercellular oedema within epidermis

Question 3

What condition presents clinically with well defined, red oval plaques on extensor surfaces ?

Answer 3

Psoriasis

Question 4

What is the Auspitz sign?

Answer 4

in psoriasis - removal of scale causes small bleeding points

Question 5

What characterises psoriasiform hyperplasia?

Answer 5

1. Regular elongated club shaped rete ridges
2. Thinning of epidermis over dermal papillae.
3. Parakeratotic (contain nuclei) scale.
4. Collections of neutrophils in scale (Munro microabscesses)

Question 6

What is psoriasis associated with?

Answer 6

Arthropathy, 5-10%

Psychosocial effects
Increased cardiovascular disease risk

Question 7

What will a positive immunofluorescence test for Lupus erythematosus show?

Answer 7

Lupus erythematosus band.

IgG deposited in basement membrane.

Question 8

What is a Heliotropic rash?

Answer 8

Peri-ocular oedema and erythema

Question 9

How does Dermatomyositis present?

Answer 9

Heliotropic rash
Erythema in photosensitive distribution.
Myositis - proximal muscle weakness.

Question 10

What is Dermatomyositis associated with?

Answer 10

In adults 25% associated with underlying visceral cancer.

Question 11

How does a heliotropic rash differ from Lupus erythematosus?

Answer 11

a heliotropic rash is negative in immunofluorescence testing

Question 12

What are Bullous diseases?

Answer 12

Formation of fluid filled blisters

Question 13

Where are the bullae located in Pemphigus and what causes them?

Answer 13

Pemphigus = Intra-epidermal bullae

IgG autoantibodies against desmoglein 3 damage the desmosomes and the epidermis falls apart.

Question 14

Where are bullous Pemphigoid found and what causes them?

Answer 14

Bullous Pemphigoid = subepidermal blisters

IgG autoantibodies against glycoprotein in basement membrane cause a split in the dermo-epidermal junction.

Question 15

What causes small intensely itchy blisters on the extensor surface in young patients?

Answer 15

Dermatitis Herpetiformis

IgA deposition in the dermal papillae
cause Neutrophil microabscesses in the dermal papillae.

Question 16

What is Dermatitis Herpetiformis associated with?

Answer 16

Coeliac disease

Question 17

What is Acanthosis Nigricans and what is it associated with?

Answer 17

Acanthosis Nigricans = dark warty lesions in armpits

associated with internal malignancy.

Question 18

What can cause Porphyria Cutanea Tarda?

Answer 18

Mutations in the UROD gene.
Hepatitis C
Alcohol abuse

Question 19

What is the commonest malignant tumour of the skin?

Answer 19

Basal cell carcinoma

metastases very rare

Question 20

What genetically inherited condition predisposes people to developing basal cell carcinomas?

Answer 20

Gorlin’s syndrome

otherwise known as Nevoid basal-cell carcinoma syndrome (NBCCS)

Question 21

What is the aetiology of basal cell carcinoma?

Answer 21

Sun exposed site, especially face

Pale skin that burns easily
Immunosuppression

Question 22

In what condition do you see rodent ulcers?

Answer 22

Basal cell carcinoma - late stage

Question 23

What are the risk factors for squamous cell carcinoma of the epidermis?

Answer 23

U.V. irradiation
Hydrocarbon exposure eg. tars, mineral oils, soot. (SCC in chimney sweeps scrotum)
Chronic scars/ulcers - Marjolins ulcer
Immunosupression

Question 24

What does a squamous cell carcinoma look like clinically?

Answer 24

Nodule with ulcerated, crusted surface.

Question 25

What is actinic [solar]keratosis?

Answer 25

Scaly lesion with erythematous base

Pre-malignant disease of squamous cell carcinoma
Dysplasia to Squamous epithelium.

Question 26

What are melanocytes derived from embryologicaly?

Answer 26

Melanocytes derive from neural crest

Question 27

How do melanocytes protect the skin from UV radiation?

Answer 27

Melanocyte’s produce melanin

- transferred to epidermal cells to protect the nucleus

Question 28

What is dysplastic naevus syndrome?

Answer 28

Families with increased incidence of melanoma
Multiple clinically atypical moles
Histologically atypical
Increased risk of developing melanoma.

Question 29

How do you tell the difference between a naevus and a melanoma?

Answer 29

ABCD

• Asymmetrical
• Borders uneven
• Colour variation
• Diameter >6mm

Question 30

How does Lentigo Maligna present clinically?

Answer 30

Slow growing, flat, pigmented patch.

Usually found on the faces of elderly people

Question 31

What is seen in Lentigo Maligna microscopically and what may happen late in the disease?

Answer 31

Proliferation of atypical melanocytes along basal layer of epidermis
+ also shows signs of chronic sun damage

Late in disease, melanocytes may invade dermis
- Lentigo maligna melanoma
with potential to metastasise.

Question 32

What is the most common form of melanoma in afro-caribbean’s?

Answer 32

Acral Lentigenous Melanoma

Question 33

Where is Acral Lentigenous Melanoma found?

Answer 33

Palms and soles, occasionally subungual.

Question 34

What is the commonest type of melanoma in Britain and how does it present clinically?

Answer 34

Superficial spreading melanoma

Early: flat macule.
Late: blue/black nodule.

Question 35

What is seen microscopically in superficial spreading melanoma?

Answer 35

Proliferation of atypical melanocytes which invade epidermis (pagetoid spread) and dermis.

Question 36

What kind of melanoma microscopically shows invasive atypical melanocytes invading the dermis to produce nodules of tumour cells?

Answer 36

Nodular Melanoma

Poor prognosis.

Question 37

What measure is used as the prognostic factor for primary melanomas?

Answer 37

Breslow thickness

Question 38

Which sites for melanomas have the worst prognosis?

Answer 38

BANS - back, arms (posterior upper), neck, scalp.

Question 39

60% of melanomas have a mutation in what gene?

Answer 39

B-Raf gene

- a proto-oncogene

Question 40

What is the treatment for Melanoma?

Answer 40

Surgery – excise primary and + lymph nodes if sentinel node positive

BRAF inhibitors- 60% melanoma’s