1. Department of Dermatology; University Hospital of Gran Canaria ‘Doctor Negrín’; 35010 Las Palmas de Gran Canaria Canary Islands Spain
2. Department of Pathology; University Hospital of Gran Canaria ‘Doctor Negrín’; Las Palmas de Gran Canaria; Las Palmas de Gran Canaria Canary Islands Spain
3. Department of Pathology; University Hospital ‘Marqués de Valdecilla’; Santander Cantabria Spain