Topical calcipotriol as a new therapeutic option for the treatment of clear cell acanthoma*

Although uncommonly diagnosed, clear cell acanthoma represents an original source of speculative interest for dermatologists. Due to its clinical variability, it is often only recognized accidentally after histology. Dermoscopy has improved the reliability of clinical diagnosis of typical clear cell acanthoma thanks to the vascular pinpoint pattern and desquamative, peripheral collarette. Generally, therapy of clear cell acanthoma is oriented towards ablative solutions, such as surgery or cryotherapy. We propose a conservative therapy, based on the application of topical calcipotriol, which has produced complete regression after 2 months and no relapse one year after the end of treatment. A dermatoscope monitored all changes of clear cell acanthoma, showing its utility not only in diagnosis but also in therapeutic follow-up. This new therapeutic approach should support an inflammatory etiology of clear cell acanthoma, although further observations are needed to confirm this.