Natural Daylight Photodynamic Therapy (NDL-PDT) is an efficacious treatment of actinic keratosis (AK). However, the use of daylight introduces uncontrolled variability that may influence the effectiveness, such as time of year, cloudiness, sunscreen application and patient behaviour [1]. An innovative satellite-based solution (SmartPDT®) is the first scientifically validated digital medical device (CE-marked Class 1) solving this [2]. The dermatologist can accurately plan and then monitor in real-time the effective (PpIX-effective) and safe (erythemal) solar radiation doses.
An observational, multicentre, prospective study of clinical practice took place in Spain from June 2022 to October 2023. Clinical teams used the SmartPDT® web-portal for monitoring either a hospital-based NDL-PDT or a home-based NDL-PDT performed by the patient using its related mobile app. Follow-up clinical evaluation was performed at 3 months.
Thirty patients were included, 5 females and 32 males, with ages ranging from 51 to 87 years old. All NDL-PDT sessions were performed according to the current clinically-accepted therapy protocol [3], so exposing patients for exactly 2 hours to sunlight independently from weather conditions. AK severity (AKASI score) was assessed before and 3 months after treatment, considering scalp, forehead, left face and right face separately.
For all body sites considered, PpIX-effective solar doses ranged from 2.98 Jeff/cm2 to 23.8 Jeff/cm2, while erythemal doses ranged from 1.9 Jeff/m2 to 61.84 Jeff/m2. Air temperature ranged from 7.3 ˚C to 39.58 ˚C. A preliminary analysis on the correlation between AKASI variation (i.e. treatment effectiveness) and monitored environmental variables was conducted and we will present its results.
This study demonstrates that a satellite-based digital system can help clinicians to optimise the overall management and effectiveness of NDL-PDT, planning and monitoring the environmental variables affecting its clinical outcomes and safety. This can help to provide a more effective and comfortable treatment with higher therapy adherence.