1. Department of Dermatology, University of California San Francisco, Mt. Zion Cancer Research Center, 2340 Sutter Street N461, San Francisco, CA 94115, USA
2. The Rudolfstiftung Hospital, Academic Teaching Hospital, Department of Dermatology, Medical University Vienna, Juchgasse 25, 1030 Vienna, Austria
3. Department of Medical Sciences, Section of Dermatology, University of Turin, Italy