Actinic keratosis
- Definition: UV-induced precancerous skin lesion that may progress to skin cancer.
- Epidemiology: occurs especially in individuals with light skin who are over the age of 50
- Etiology: sun exposure (e.g., from working outdoors)
- Lesion
- Occurs on areas of sun-exposed skin
- Initially: small lesion (papule or plaque) with rough surface (sandpaper-like texture)
- Later: Lesions grow and become brown or erythematous and scaly.
- Hyperkeratosis in such lesions may become prominent and form cutaneous horns.
- Prognosis
- Lesions may either regress, persist, or progress to cutaneous squamous cell carcinoma (SCC).
- The degree of epithelial dysplasia determines the risk of cutaneous squamous cell carcinoma.