A Multicenter Clinical Study of Expected and Unexpected Side Reactions During and After Skin Cancer Treatment by Photodynamic Therapy

Abstract

Photodynamic therapy (PDT) has been widely used for oncologic indications, especially nonmelanoma skin cancer such as superficial and nodular basal cell carcinoma (BCC). We present a multicenter clinical study conducted between 2012 and 2014 analyzing the adverse reactions during and after PDT with a standardized protocol in 866 lesions. A total of 728 patients with positive clinical and histopathological diagnosis for BCC with up to 2 cm diameter were treated. The procedure consisted of curettage and topical application of cream containing 20% methyl 5-aminolevulinate. The illumination (630 nm and 150 J/cm²) was performed 3 hours after the cream application. The expected and unexpected effects observed were pain, healing, and inflammatory reactions. The pain intensity was correlated with the anatomical localization of the lesion. The patients reported a higher intensity of pain in lesions located on the head and neck rather than on the trunk and limbs. The number of sessions also influenced the pain response. A total of 83% of patients showed perfect healing and the other 17% presented abnormal healing. PDT plays an important role in BCC because of its low cost, ease of use, and low rate of side effects.