aetiology
Last reviewed 01/2018
- exposure to ultraviolet light:
- usually occurs in fair-skinned, elderly people
- may develop from pre-existing solar keratosis
- chronic exposure to industrial carcinogens
- arsenic, chromium compounds
- ionising radiation
- soot (carcinoma of the scrotum in chimney sweeps),
- also tar, pitch, oils
- chronic inflammation (Marjolin's ulcer):
- margins of osteomyelitic sinuses
- margins of long-standing ulcers
- lupus vulgaris
- genetic predisposition:
- xeroderma pigmentosum
- albinism
- premalignant conditions:
- Bowen's disease
- leukoplakia
- erythroplasia of Queyrat
- immunosuppression e.g. renal transplant patients