Actinic keratoses (AKs) are red or brown flat scaly lesions that are rough to touch. They occur when sufficient chronic sun exposure allows for genetically damaged epidermis to exhibit clinical lesions. All of the skin is affected (field change) with the most damaged areas expressed as discrete lesions of variable thickness and scale. AKs can be itchy, scaly, rough, sore or bleed. Shallow ulceration can develop as well as persistent sterile pustulation. An uncertain but small percentage transform into squamous cell carcinoma (SCC). This is more likely to happen in immunocompromised patients, those with a previous SCC, elderly patients and extensive moderate/severe AKs. Not all AKs need treating but they should be identified.
Advice on available treatments, sun protection, and risk of skin cancer and skin self-examination should be given. Since AKs are a marker for all types of skin cancer, the patient should be inspected on the arms, lower legs, chest, upper back, neck and head as a bare minimum examination.
All year round regular sun protection (which may include sunblock) will reduce the frequency of new visible lesions developing and mild lesions will regress.
The vast majority of AKs can be managed in primary care. To properly manage AKs, it is best to separate field change from separate lesions and stratify into mild, moderate and severe cases.
Red flag signs that should prompt referral to secondary care are:
- Immunosuppressed patients
- Bowen's disease
- Painful lesions
- Cutaneous horns
- Rapidly growing lesions
- Deeply ulceration lesions and solitary lesions without convincing evidence of surrounding chronic sun damage
- Pigmented facial lesions may also be very difficult to tell apart from lentigo maligna
Field change treatment
Areas of treatment should not exceed 5cm x 5cm. Divide into sections for larger fields
Sun-protection and Self-examination advice should be given to all patients
Differential diagnosis: seborrhoeic keratosis; dermatitis; Bowen's and SCC
Mild to Moderate AKs
Fluorouracil cream 5%
- Apply thinly to the affected area once or twice daily; usual duration of initial therapy 3–4 weeks
- Local specialist advice: areas of treatment should not exceed 5cm x 5cm, divide into sections for larger fields. Refer to the SPC for Efudix 5% cream for maximum area of treatment at one time
- Caution: flammable
- Patients need to be counselled about the inflammatory reaction they will get which can be severe. 1% hydrocortisone ointment can be used but if the reaction is severe please contact the Dermatology department
- See section 13.8.1 Sunscreen preparations (photodamage)
Moderate to Severe AKs
Fluorouracil cream 5%
Apply thinly to the affected area once or twice
daily; usual duration of initial therapy 3–4 weeks
Local specialist advice: areas of treatment should
not exceed 5cm x 5cm, divide into sections for larger fields. Refer to the
SPC for Efudix 5%
cream for maximum area of treatment at one time
- Caution: flammable
Patients need to be counselled about the
inflammatory reaction they will get which can be severe. 1% hydrocortisone ointment
can be used but if the reaction is severe please contact the Dermatology
See section 13.8.1 Sunscreen preparations (photodamage)
Imiquimod cream 5%
- Apply to lesions 3 times a week at night for 4 weeks and leave on skin for approximately 8 hours; assess response after a 4 week treatment-free interval; repeat 4-week course if lesions persist; maximum 2 courses
- See section 13.7 Preparations for warts and callouses
Methyl-5-aminolevulinate cream (Metvix®) with Photodynamic therapy (PDT)
- Cream 160mg/g
- With Photodynamic Therapy. Review response 3 months post treatment. Re-treat or refer if palpable lesions present
- Available in secondary or intermediate care
- For the treatment of AKs, Bowens disease and superficial BCC
- Useful in delicate skin at risk of ulceration and poor wound healing or where an alternative treatment would be disfiguring
- Also useful for AK induced scalp erosive pustulosis
Imiquimod 3.75% (Zyclara®)
The routine commissioning of imiquimod 3.75% (
is not accepted in Devon for the treatment of actinic keratosis (see Commissioning Policy for more details)
Individual AK lesions
Sun-protection and self-examination advice
- Available in primary, intermediate and secondary care. Two freeze-thaw cycles of 10 seconds. Hyperkeratotic lesions unlikely to respond without debridement. Patient at risk from permanent hypo pigmentation or atrophic scarring.
Fluorouracil 5mg/g (0.05%) with salicylic acid 100mg/g (10%) cutaneous solution
Curettage and cautery (with pathology)
- Hyperkeratotic lesions, cutaneous horns and where the index of suspicious of SCC transformation is high.
- Always send each curetted specimen in a separate histology pot for pathology.
- Review at 6 weeks post treatment. Re-treat or refer if lesion not resolved
Combination therapy should be used when the patient presents with both individual AKs and field change, although most topical agents will deal with mild to moderate individual lesions.
13. Skin >
Treatment of actinic keratoses
- First line
- Second line