A retrospective analysis of real-life practice of off-label photodynamic therapy using methyl aminolevulinate (MAL-PDT) in 20 Italian dermatology departments. Part 1: inflammatory and aesthetic indications

Experimental investigations have demonstrated that photodynamic therapy (PDT) with methyl aminolevulinate (MAL) may be a useful treatment in several inflammatory skin disorders and aesthetic indications. To assess the effectiveness, tolerability and safety of off-label MAL-PDT in daily clinical practice in 20 Italian hospital centers, a retrospective observational study of medical records of patients treated for off-label inflammatory and aesthetic indications was carried out. In all patients standard treatment options had been either ineffective, unacceptably toxic, or medically contraindicated. Clinical data regarding 221 patients affected by 22 different diseases were collected. The most common off-label indication was acne vulgaris, with >75% improvement in 72.8% of patients. Other disorders of the sebaceous gland, i.e. acne rosacea, hidradenitis suppurativa and sebaceous hyperplasia, were less responsive. Alopecia areata did not show any improvement. Granuloma annulare and necrobiosis lipoidica showed marked or moderate response in the majority of treated patients. The rate of patients with complete remission was lower for inflammatory skin disorders with hyperkeratosis, i.e. psoriasis (6/17) and porokeratosis (3/16). The efficacy for lichenoid dermatoses was dependent on the clinical variant (erosive and scleroatrophic were more responsive than hypertrophic). Only 1 of 6 patients with Zoon balanitis had a marked improvement. MAL-PDT of venous leg ulcers, photo-aging and hypertrophic scars led to a marked remission in 3/5, 3/6 and 5/8 patients, respectively. The treatment had to be interrupted because of strong pain and burning in 24 patients. Long term adverse events were not registered. Most patients with marked improvement had lasting remission with overall excellent cosmetic outcomes. The present findings demonstrate a high interest in off-label uses of MAL-PDT for inflammatory skin disorders. According to the observed clinical responses, safety, and favorable cosmetic results, MAL-PDT seems to have a potential therapeutic role for the treatment of granulomatous dermal disorders and follicular inflammatory diseases whereas results in other conditions are less encouraging.