The emerging role of 5-ALA-PDT in dermatology: is PDT superior to standard treatments?

Several open studies report the efficacy of topical photodynamic therapy (PDT) in the treatment of non-melanoma skin cancer and pre-cursor lesions. For a new therapy to change clinical practice, comparison studies with standard therapies are required, assessing efficacy, adverse events and cosmetic outcome. This review considers the evidence for using topical PDT over standard therapies in non-melanoma skin cancer. Limited data indicates topical PDT to be superior to cryotherapy and equivalent to topical 5-fluorouracil in clearing non-hyperkeratotic actinic keratoses, and to achieve a superior cosmetic outcome. Topical PDT is superior to topical 5-fluorouracil, and equivalent to cryotherapy, in the treatment of squamous cell carcinoma in situ (Bowen's disease), again with fewer adverse reactions. Similarly, PDT is as effective as cryotherapy for basal cell carcinoma, but with superior healing and cosmesis. PDT may be particularly advantageous for large and/or multiple lesions and for those in sites where disfigurement or poor healing from conventional therapies is a particular risk. There remains a lack of comparison data concerning routine surgery, curettage, and radiotherapy, but topical PDT would appear as effective as, and in certain aspects superior to, standard therapies in the treatment of non-melanoma skin cancer.