1. Department of Medicine and Surgery, University of Perugia, 05100 Terni, Italy
2. Dermatologic Clinic, S. Maria Hospital, University of Perugia, 05100 Terni, Italy
3. Department of Surgery, S. Maria Hospital, 06129 Perugia, Italy
4. Department of Surgery, Sapienza University, 00189 Rome, Italy
5. Section of Pathology, Department of Medicine and Surgery, University of Perugia, 05100 Terni, Italy
6. Department of Surgery, University of Milan, 20122 Milan, Italy