Skin Pathology

Question 1

structure of the skin

Answer 1

EPIDERMIS - stratified squamous epithelium

DERMIS - CT later providing strength and elasticity

The basement membrane separates the epidermis and dermis

Melanocytes are found scattered along the basal layer of the epidermis, just ABOVE the basement membrane

Question 2

Malignant melanoma risk factors

Answer 2

fair skin
sun exposure
use of sunbeams

Question 3

Malignant melanoma epidemiology

Answer 3

5th most common cancer in the UK
2nd most common cancer in adults ages 25-49
incidence in uk rising faster than any other common cancer

Question 4

Aural melanoma

Answer 4

occurs on palms, soles and under nail beds
most common melanoma in asian and black ethnic groups
does not appear to be linked to sun exposure

Question 5

suspicious signs of skin lesions

Answer 5

Asymmetry
Border
Colour
Diameter

Question 6

Breslow thickness

Answer 6

thickness of tumour measured in millimetres, a VERY IMPORTANT prognostic factor

melanomas <0.75mm have a 98% 5y survival

melanomas >1.5mm have a 40-60% 5y survival

Question 7

What is the most common type of skin cancer

Answer 7

BCC - 70%

Question 8

BCC risk factors and appearance

Answer 8

same risk factors as melanoma - fair skin, UV exposure

nodule with a pearly appearance. may be a central umbilication or ulceration

Question 9

Squamous cell carcinoma risk factors

Answer 9

fair skin
UV exposure
immunosuppression
chronic skin ulcers (Marlin ulcers)

tend to grow faster than BCC

Question 10

Actinic keratosis

Answer 10

common in the elderly
fair skin and sun exposure and risk factors
small brown, dry, scaly lesions in sun exposed sites e.g. scalp
dysplasia but no invasion through the basement membrane - PRE CANCER