Actinic Keratosis

Actinic Keratosis – Treatment Options

Introduction
Actinic keratosis (AK), also known as solar keratosis, is a common precancerous skin lesion caused by cumulative ultraviolet (UV) radiation exposure. It presents as rough, scaly, erythematous patches or plaques on sun-exposed areas such as the face, scalp, forearms, and hands. AK has the potential to progress to squamous cell carcinoma (SCC), making early recognition and treatment essential. Management focuses on lesion eradication, field therapy for widespread damage, and long-term photoprotection.

1. Local (Lesion-Directed) Therapies

• Cryotherapy (liquid nitrogen): Most common method; induces tissue necrosis, effective for isolated lesions.

• Curettage ± electrocautery: Scraping off lesions, sometimes followed by cauterization.

• Surgical excision: For hypertrophic or suspicious lesions to rule out invasive SCC.

• Laser therapy (CO₂ or Er:YAG): Useful in resistant lesions or for cosmetic outcomes.

2. Topical (Field-Directed) Therapies

• 5-Fluorouracil (5-FU):

  • Cream (0.5–5%) applied once or twice daily for several weeks.

  • Causes inflammation, erosion, then healing with lesion clearance.

• Imiquimod:

  • Immune response modifier stimulating interferon-α production.

  • Cream (3.75% or 5%) applied 2–5 times weekly for several weeks.

• Diclofenac sodium 3% gel:

  • Anti-inflammatory, applied twice daily for 60–90 days.

  • Less irritating but slower effect.

• Ingenol mebutate (withdrawn in some markets due to safety concerns):

  • Applied for 2–3 days; induces rapid cytotoxic and immune-mediated clearance.

3. Photodynamic Therapy (PDT)

• Involves topical photosensitizer (aminolevulinic acid or methyl aminolevulinate) applied to lesions, followed by light activation.

• Effective for multiple lesions and field treatment; provides excellent cosmetic results.

4. Adjunctive and Preventive Measures

• Photoprotection:

  • Daily broad-spectrum sunscreen (SPF ≥ 30).

  • Protective clothing and avoidance of peak sun exposure.

• Retinoids (topical or systemic): May be used in high-risk or immunosuppressed patients to reduce recurrence.

• Regular dermatologic surveillance: To detect recurrence or malignant transformation early.

5. Multidisciplinary Care

• Dermatologist: For diagnosis, treatment selection, and follow-up.

• Oncologist: If lesions progress to invasive squamous cell carcinoma.

• Primary care physician: Reinforce sun safety and coordinate long-term monitoring.