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.