1. Department of Dermatopathology; St John's Institute of Dermatology, St Thomas' Hospital; London UK
2. St John's Institute of Dermatology; St Thomas' Hospital; London UK
3. Dermatopathology Laboratory, Department of Dermatology; Universita' degli Studi di Milano; Milano Italy
4. Oncology Department, Anatomic Pathology Unit; Gaetano Rummo General Hospital; Benevento Italy
5. Dermatopathology; University Hospital Città della Salute e della Scienza; Turin Italy
6. Manuraj Singh, Department of Dermatology; St George's University Hospital; London UK
7. Iris Zalaudek, Division of Dermatology; Non-Melanoma Skin Cancer Unit, Medical University of Graz; Graz Austria