What are the treatment options for actinic keratosis?

Treatment Options for Actinic Keratosis

5-fluorouracil (5-FU) is strongly recommended as the first-line treatment for actinic keratosis, particularly for patients with multiple lesions, with cryosurgery recommended for thicker individual lesions. 1

First-Line Treatment Options

Field-Directed Therapies (for multiple lesions)

1. 5-Fluorouracil (5-FU)

   • Formulations:
     • 5% cream: Applied twice daily for 2-4 weeks
     • 0.5% cream: Applied once daily for 1-4 weeks
   • Complete clearance rate: 70% at 12 months 1
   • Most effective field treatment according to high-quality evidence 2
   • Common side effects: Soreness, redness, crusting 1

2. Imiquimod

   • Dosing: 5% cream applied 2-3 times weekly for 16 weeks 1, 3
   • Complete clearance rate: 44-46% 3
   • FDA approved for immunocompetent adults with AK on face or scalp 3

3. Tirbanibulin

   • Dosing: 1% ointment applied once daily for 5 consecutive days
   • Complete clearance rate: 49% at day 57 1

4. Diclofenac

   • Dosing: 3% gel applied twice daily for 60-90 days
   • Complete clearance rate: 50% 1
   • Lower morbidity than 5-FU but less effective overall 1, 4

5. Photodynamic Therapy (PDT)

   • Complete clearance rates: 70-89% 1
   • Especially effective for confluent AKs on face and scalp
   • Often used in combination with other treatments for enhanced efficacy 4

Lesion-Directed Therapy (for individual lesions)

1. Cryosurgery
   • Complete response rate: 75% 1
   • Duration of freeze: 5-20 seconds for most lesions, >20 seconds for thicker lesions 1
   • Particularly effective for thicker, individual lesions 1, 5

Treatment Selection Algorithm

Based on Lesion Severity

1. Grade 1 (Mild) Lesions

   • Consider emollients and sunscreen alone
   • Any treatment option is effective 1

2. Grade 2 (Moderate) Lesions

   • First choice: 5-FU
   • Alternatives: Imiquimod or PDT 1

3. Grade 3 (Severe) Lesions

   • Cryotherapy with longer freeze times
   • Consider curettage 1

Based on Body Location

• Face/Scalp/Ears: Cryosurgery, 5-FU, imiquimod 1
• Periocular: Cryosurgery with contact probe (avoid topicals) 1
• Below Knee: Consider diclofenac or PDT 1
• Hands: May require extended periods of topical therapy 1

Combination Approaches

• 5-FU followed by cryosurgery is recommended for resistant lesions 1
• Field therapy (treating entire area) followed by lesion-targeted therapy for specific recurrent/resistant AKs is increasingly popular 5
• PDT used adjunctively with other modalities shows enhanced improvement 4

Important Clinical Considerations

• Sub-clinical AK lesions may become apparent during treatment with topical therapies like imiquimod (48% of patients experience an increase in visible lesions during treatment) 3
• Patients should minimize sun exposure during treatment and use sunscreen 3
• Treatment areas should be washed with mild soap and water 8 hours after application of topical medications 3
• Local skin reactions are expected with most treatments and may require rest periods 3

Treatment Pitfalls to Avoid

1. Extending treatment beyond recommended duration

   • Treatment periods should not be extended beyond recommended timeframes (e.g., 16 weeks for imiquimod) due to missed doses 3

2. Inadequate follow-up

   • Regular follow-up is essential as AKs can recur and new lesions may develop 1

3. Neglecting sun protection

   • Consistent sun protection is crucial to prevent new lesions 1, 3

4. Failure to recognize treatment failure

   • Lesions that fail to respond to appropriate therapy require further evaluation, including possible biopsy 1

5. Overlooking field cancerization

   • Treating only visible lesions may miss subclinical disease; field therapy addresses both visible and invisible lesions 5