25 patients, with phototype 1 to 3, with grade I-II AK of the scalp will be treated. Only patients with a minimum of 9 clinically diagnosed grade I and II AK lesions of the scalp (according to the classification of Olsen) suggesting the existence of field cancerization, will treated with SDL-PDT (simulated daylight Photodynamic Therapy) using the Dermaris® (Surgiris, France) and therefore included in the study after application of MAL cream (Metvix ®, Galderma, Switzerland) to the treatment area. After debridment of all treated areas with sandpaper, Metvix will be applied and illuminated with with Dermaris 10 minutes later (leading to drug-light interval (DLI) of 10 minutes) with an irradiance of 2.9 mW/cm2 and a duration of 35 minutes The primary endpoint will be the rate of patients with less than two AK lesions at six-month post-treatment. Secondary endpoints will include scores of pain, erythema, crusts, discomfort and during or/and post the treatment.~A ﬁrst follow-up visit will be scheduled seven days after the treatment. At this visit, crusts will be clinically rated by a dermatologist, while patients scored discomfort they had experienced during the six-day post-treatment. At the second follow-up visit conducted three months after the treatment, AK lesions will be counted by a dermatologist without differentiation between new and recurrent lesions. A second SDL-PDT using the Dermaris will be performed on the day if AK lesions are still present. At last, in case of remaining AK observed at 6 month follow up, a third treatment session with the same parameters will be carried out.~The study is approved by the Ethical clinical committee of the Centre Dermatologique du Roy and conducted in accordance with the ethical principles of the Declaration of Helsinki (2008) and the International Conference on Harmonisation - Good Clinical Practices and in compliance with local regulatory requirements.
This clinical study aims aims to evaluate the clinical outcomes of SDL-PDT (simulated daylight Photodynamic Therapy) using the Dermaris in patients treated for AK lesions of the scalp at our medical dermatology center using only 35 minutes low-intensity light exposure.