1. Dermatology Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
2. Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
3. Division of Diagnostic Haematopathology, European Institute of Oncology IRCCS, 20139 Milan, Italy
4. Research Unit of Dermatopathology, Medical University of Graz, 8036 Graz, Austria
5. Dermatopathology Laboratory San Gallicano, Dermatological Institute IRCCS, 00144 Rome, Italy
6. Dermatology Unit, IRCCS AUBO, 40138 Bologna, Italy
7. Department of Medical and Surgical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, Italy