Photodynamic therapy using a novel irradiation source, LED lamp, is similarly effective to photodynamic therapy using diode laser or metal‐halide lamp on DMBA ‐ and TPA ‐induced mouse skin papillomas

Photodynamic therapy ( PDT ) is useful for superficial skin tumors such as actinic keratosis and Bowen disease. Although PDT is non‐surgical and easily‐performed treatment modality, irradiation apparatus is large and expensive. Using 7, 12‐dimethylbenz[a]anthracene ( DMBA ) and 12‐ο‐tetradecanoylphorbol‐13‐acetate ( TPA )‐induced mouse skin papilloma model, we compared the efficacy of TONS 501‐ and ALA ‐ PDT with a LED lamp, a diode laser lamp or a metal‐halide lamp on the skin tumor regression. TONS 501‐ PDT using 660 nm LED lamp showed anti‐tumor effect at 1 day following the irradiation and the maximal anti‐tumor effect was observed at 3 days following the irradiation. There was no significant difference in the anti‐tumor effects among TONS 501‐ PDT using LED , TONS 501‐ PDT using diode laser, and 5‐aminolevulinic acid hydrochloride ( ALA )‐ PDT using metal‐halide lamp. Potent anti‐tumor effect on DMBA ‐ and TPA ‐induced mouse skin papilloma was observed by TONS 501‐ PDT using 660 nm LED , which might be more useful for clinical applications.