Actinic Keratosis

KEY FEATURES

• Actinic keratoses are considered premalignant, but 1:1000 lesions/year progresses to squamous cell carcinoma

CLINICAL FINDINGS

• Actinic keratoses are small (0.2–0.6 cm) papules—flesh-colored, pink, or slightly hyperpigmented—that feel like sandpaper and are tender to palpation

• They occur on sun-exposed parts of the body in persons of fair complexion

DIAGNOSIS

• Clinical

• Differential diagnosis

  • Squamous cell carcinoma

  • Bowen disease (squamous cell carcinoma in situ)

  • Nonpigmented seborrheic keratosis

  • Psoriasis

  • Seborrheic dermatitis

  • Seborrheic keratosis

  • Paget disease

TREATMENT

• Liquid nitrogen provides rapid eradication of lesions, which crust and disappear in 10–14 days

• Topical agents may be considered in patients with multiple lesions in one area (eg, forehead, dorsal hands) and include

  • Fluorouracil

  • Imiquimod

  • Ingenol mebutate

• Photodynamic therapy can be effective in refractory cases

• Combination therapy with fluorouracil and calcipotriene creams may be clinically beneficial

• Lesions that persist or recur should be evaluated for possible biopsy