What is the role of field-directed therapy in the treatment of actinic keratosis? Part 2: Commonly used field-directed and lesion-directed therapies.

Actinic keratosis (AK) constitutes the initial epidermal lesion in a disease continuum that may potentially progress to invasive squamous cell carcinoma (SCC). A number of treatment options are available to clear lesions and thus reduce the risk for progression to SCC. Field-directed therapies are primarily used to clear multiple AKs and subclinical lesions. Part 1 of this review explaining the role of field-directed therapy for the treatment of AK discussed the unmet needs with current therapies and the investigational agents that are being developed to fill treatment gaps. Part 2 will mainly focus on field-directed therapies that currently are available for AK, such as resurfacing procedures, patient-administered topical therapy, and photodynamic therapy (PDT), as well as lesion-directed therapy, which is used to clear discrete lesions in relatively small numbers.