The objective of this protocol is to compare the efficacy of the topical application of MAL at concentrations of 8% and 16%, mediated by red light, as well as to evaluate the impact of different incubation times (1 or 3 hours) in the treatment of actinic keratoses on the face, with a 6-month follow-up. This parallel-arm, 6-month follow-up randomized controlled clinical trial will consist of 4 groups: G1 - Control Group - MAL 16% irradiated with 643nm and 75J/cm² and 3-hour incubation time (n=36), G2 - MAL 16% and 1-hour incubation (n=36), G3 - MAL 8% - 3 hours (n=36), and G4 - MAL 8% - 1 hour (n=36). The researcher conducting the collection and the participant will be blinded to the interventions. The primary outcome will be the complete remission of the lesion at 6 months. Secondary outcomes will include treatment success (75% reduction in the initial number of lesions), recurrence rate, emergence of SCC, incidence of adverse effects, and improvement in skin texture, wrinkles, and pigmentation using a validated scale. All outcomes will be assessed at 30 days, 3, and 6 months. Quality of life will be evaluated using the Actinic Keratosis Quality of Life questionnaire (AKQoL) at 6 months.
Individuals of both sexes,
Aged between 40 and 90 years,
Fitzpatrick skin phototypes I to IV,
Photodamaged skin with at least five clinically evident actinic keratosis lesions on the face to be treated,
Clinically diagnosed infiltrative lesions, as the gold standard treatment is surgical with histopathological evaluation of the lesion (surgery will be performed at no cost to the participant), who will receive guidance and referral for appropriate treatment.
Photosensitive diseases, such as systemic lupus erythematosus, dermatomyositis, porphyria, among others.
History of arsenic exposure,
Known allergy to MAL or similar photosensitizing agents,