1. Dermatology Section Department of Medical, Surgical and Neurological Science S. Maria alle Scotte Hospital University of Siena Siena Italy
2. Department of Pathology University Hospital of St‐Etienne Saint‐Etienne France
3. Department of Dermatology Azienda Ospedaliera Spedali Civili di Brescia Brescia Italy
4. Department of Dermatology University Hospital of St‐Etienne Saint‐Etienne France