Polypodium leucotomos supplementation in the treatment of scalp actinic keratosis: could it improve the efficacy of photodynamic therapy?

BACKGROUND: Actinic keratoses (AKs) are a common premalignant skin condition. Many treatments are available for AKs. Photodynamic therapy (PDT) is one of the most effective treatments. However, major concerns exist on the possibility of PDT-induced DNA-mutagenesis/immunosuppression, leading to AKs recurrence/treatment failure. An extract (PLE) from the fern polypodium leucotomos reduces UV-induced immunosuppression and mutagenesis.

OBJECTIVE: To assess the ability of PLE to enhance the efficacy of PDT treatment, reducing AKs recurrence on the scalp.

MATERIALS AND METHODS: Thirty-four bald patients presenting at least two AKs on the scalp were alternatively assigned to two groups. Both groups underwent two PDT-sessions one-week apart. The first group began oral PLE supplementation one week after the last PDT session. Evaluation of the effect of PLE supplementation was performed by direct inspection of the bald areas, lesions count, and photodynamic diagnosis assessment at 2 and 6 months.

RESULTS: Both groups were homogeneous in terms of skin phototype and previous UV exposure. Mean age was 75.7 ± 7.8 years and 76.5 ± 5.5 years, respectively. Both treatment modalities were successful in reducing AKs number (p < .001). However, PLE supplementation increased clearance rate compared with PDT alone (p = .040).

CONCLUSION: Polypodium leucotomos improves PDT clearance and decreases AK recurrence rate at 6 months, suggesting its use as a complementary agent in the treatment of field cancerization.