J C Cardoso1, G Tchernev2, A A Chokoeva3. 1. Dermatology and Venerology Department, University Hospital of Coimbra Praceta Mota Pinto 3000 075, Coimbra, Portugal. 2. Polyclinic for Dermatology and Venerology, Saint Kliment Ohridski University, Medical Faculty, University Hospital Lozenetz, Koziak Street 1, 1407 Sofia, Bulgaria. georgi_tchernev@yahoo.de. 3. Onkoderma-Polyclinic for Dermatology and Dermatologic Surgery, General Skobelev 26, Sofia, Bulgaria.