Photodynamic Therapy in Refractory Mycosis Fungoides: A Prospective, Open-Label Study

Abstract

Background:Case reports suggest photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an effective treatment for refractory mycosis fungoides (MF). No prospective trials have examined the use of ALA-PDT in MF. Objective:We aimed to assess the efficacy of ALA-PDT in refractory MF. Methods:This was a prospective study at Mayo Clinic in Scottsdale, Arizona in patients ≥ 18 years with plaque-stage treatment-refractory MF. Monthly sessions of ALA with blue light PDT were administered for up to six months. Responses were measured by Composite Assessment of Index Lesion Severity (CAILS) and Physician Global Assessment (PGA). Ad hoc analysis with modified CAILS (mCAILS) was performed, eliminating hyperpigmentation from scoring. Results:Eleven patients (30 total lesions) were treated. Six patients completed the trial per protocol. Objective response rates were 36.4% by PGA (10.9-69.2%), 18.2% by CAILS (2.3-51.8%), and 36.4% by mCAILS (10.9-69.2%). Limitations:Five patients did not complete all six PDT cycles per protocol, possibly accounting for reduced efficacy. Conclusion:ALA-PDT with blue light irradiation was moderately effective and well tolerated in refractory plaque stage MF. Lower response rates compared to similar trials may be partially explained by utilization of strict lesional assessment criteria and other variations in methodology. Disclosures Mangold: MiRagen:Research Funding;Sun Pharma:Research Funding;Elorac:Research Funding;Kirin:Membership on an entity's Board of Directors or advisory committees;Solagenix:Research Funding. OffLabel Disclosure: Photodynamic therapy is a two-step therapy in which a drug that acts as a photosensitizer is administered to target a diseased tissue, followed by illumination with visible light to activate the drug and destroy the target tissue. PDT has been used to treat internal cancers as well as treatment of cancer and precancer of the skin.