Key recommendations
Key recommendations: physical and systemic therapies
- Education at the outset of using physical therapies is important to ensure a full understanding of the side- effects, which can be marked and include scarring and altered pigmentation.
- Cryosurgery is a flexible and effective form of lesion- based physical therapy that removes the patient involvement in their own care and requires administration in a service with cryosurgery.
- Curettage can be warranted for thicker (grade 3) AKs, where they are resistant to topical therapy and where there is suspicion that they may represent early SCC. Histology must always be obtained. Diagnostic biopsy may be warranted on the same basis, but is subject to sampling error.
- PDT is an effective treatment for confluent AKs, such as on the scalp, which are difficult to manage or resistant to treatment in the absence of invasive disease.
- PDT has low scarring potential and less risk of poor healing in comparison with other physical therapies at vulnerable sites such as the lower leg.
- Pre-treatment with topical therapy can increase the efficacy of physical therapies.
- Failure of an individual lesion to respond to physical therapy indicates a need for further evaluation. This could include formal excision.
- Systemic therapy is usually given in the context of multiple grade 3 AKs, a history of serial SCCs and immuno- suppression. Therapy might be preventive with a retinoid and should be undertaken as part of a multidisciplinary decision, which might include alternatives such as the reduction of immunosuppression.
Key recommendations: special sites
- Poor healing sites such as below the knee in the elderly require flexible regimens, heightened supervision and consideration of less destructive treatments such as PDT.
- The ears are commonly affected by AK and require attention early in respect to all modalities of treatment, including preventive action with a broad-brimmed hat and sunscreen.
- Grade 3 AKs on the ear may warrant curettage early to obtain histology and avoid missed early SCC.
- The skin of the dorsum of the hands can be more resistant to treatment than the head and neck, and warrants extended periods of topical therapy.
- All licensed treatments include warnings about use near the eye. Periocular AK needs careful assessment in secondary care. Topical treatments may be possible, but clear guidance and supervision are needed.
Treatment failure
All treatments have some risk of failing to achieve clearance of an individual lesion. Where this is the case, the reason for failure needs assessment, where one of the possible explanations might be that the diagnosis is incorrect. Lesions within the differential diagnosis of AK include SCC in situ, invasive SCC, seborrhoeic keratosis, actinic porokeratosis, viral wart and others. Depending on the outcome of this clinical assessment, treatment might be escalated in intensity, duration or type, or the lesion might be biopsied or treated surgically.
An alternative interpretation of failure is that the patient continues to get new AKs. This is not true failure, but more an illustration of the nature of the disease. Once someone is diagnosed with AK, they are likely to need intermittent, life- long treatment. (16)