Photodynamic therapy combined with CO2 laser for the treatment of seborrheic keratosis in the auricle: A case report

Seborrheic keratosis(SK) is a very common skin tumor which is mostly frequently observed in the trunck, head, neck. SK in the auricle is rare and this condition should be excluded the possibility of malignancy by pathologic diagnosis. We report a case of 66-year-old man who presented with a brownish, papillomatous, verrucous mass in the auricle for the past seven years, which began to growing faster during the previous year. Dermoscopy and histopathological examination were performed and the patient was diagnosed with SK. He was treated with the carbon dioxide(CO2) laser and aminolevulinate photodynamic therapy (ALA-PDT). The CO2 laser was used for the removal of the thick hypertrophic lesions and to enhance the transdermal absorption efficiency of ALA. A 20 % ALA cream(118 mg/cm2) was applied to his lesion and sealed for 3 h without light, followed by irradiation with 630-nm LED light (96 J/cm2, 80 mw/cm2). We use fluorescent diagnosis with aminolevulinic acid to define the tumor margins at the first session of ALA-PDT. After 4 sessions of ALA-PDT, the lesion was completely removed and did not recur. Therefore, we consider that ALA-PDT combined with CO2 laser is a safe and effective choice for the treatment of seborrheic keratosis in the auricle.