Dysplastic/pre-malignant skin lesions

Question 1

What is actinic (solar) keratoses?

Answer 1

Common on sun-exposed areas of fair skinned individuals in later life, especially bald scalps

=> scaly, erythematous papule or patches, feel gritty & rough

=> surrounding skin = chronic sun damage with wrinkles and solar lentigo

=> small % of actinic keratoses undergo malignant change into SCC

=> Treat with: cyrotherapy, curettage & cautery

Question 2

What Bowen’s disease (intraepithelial carcinoma)?

Answer 2

Indolent form of intraepidermal (in situ) SCC that rarely progresses to invasive disease

=> affects lower legs in fair-skinned women or torso of men

=> caused by chronic UV exposure

=> slowly enlarging, well-demarcated, scaly red patch or plaque resembling psoriasis

=> genital’s bowen disease linked to HPV-16

Question 3

What is keratoacanthoma?

Answer 3

Rapidly growing epidermal tumours that develop as red papule with central crater-like, crusty keratinous plug

=> occur on sun-exposed skin in later life

=> 2-3cm in diameter

=> may regress spontaneously after ~3months, leaving a pitted scar

=> usually excised because difficult to differentiate between SCC