The purpose of this study is to compare the efficacy of photodynamic therapy with 5-aminolevulinic acid and intense pulsed light vs absence of treatment for actinic keratoses.

This study seeks to evaluate the efficacy of photodynamic therapy with 5-aminolevulinic acid and intense pulsed light vs. absence of treatment for actinic keratoses

Inclusion Criteria:

Age greater than or equal to 18 years

• Have a t least 4 nonhypertrophic AK lesions on the body
• The subjects are in good health
• The subject has the willingness and the ability to understand and provide informed consent for the use of their tissue and communicate to the investigator

Exclusion Criteria:

• Subjects who are pregnant or lactating
• Subjects with a history of cutaneous photosensitivity or porphyria, hypersensitivity to porphyrins, or photodermatosis
• Subjects with use of photosensitizing drugs within 1 week of study start
• Subjects with use of topical medications such as corticosteroids, alpha-hydroxyacids or retinoids 2 weeks before study entry
• Subjects with systemic steroid therapy within 4 weeks before study entry
• Subjects who received previous treatment of target AKs
• Subjects with systemic treatment with chemotherapeutic agents, masoprocol (Actinex), immunotherapy, or retinoids within 2 months of study entry
• Subjects with prior history of hypersensitivity reactions to lidocaine
• Subjects who are unable to understand the protocol or to give informed consent