1. Department of Dermatology, Azienda Sanitaria Toscana Centro, University of Florence, Florence, Italy
2. Department of Health Sciences, Clinical Pharmacology and Oncology Unit, University of Florence, Florence, Italy
3. Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
4. Cancer Registry of Norway, Oslo, Norway
5. Surgical Department Melanoma, European Institute of Oncology, Milan, Italy
6. Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy