1. CARADERM, French Network of Rare Cutaneous Cancer Lille France
2. Department of Pathology University Hospital of Tours Tours France
3. ‘Biologie des infections à polyomavirus’ Team UMR1282 INRAE, University of Tours Tours France
4. Department of Biopathology Center Léon Bérard Lyon France
5. Centre Léon Bérard, Cancer Research Center of Lyon, Equipe Labellisée University of Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286 Lyon France
6. Department of Pathology Hôpital Cochin, AP‐HP, AP‐HP Centre – Université Paris Cité Paris France
7. Faculté de Médecine University Paris Cité Paris France
8. Department of Pathology University Hospital of Poitiers, University of Poitiers, LITEC Poitiers France
9. Department of Dermatology, Venereology and Allergology University Hospital Würzburg Würzburg Germany
10. Aix‐Marseille Univ, INSERM, MMG, U1251, Marmara Institute Marseille France
11. Laboratory of Molecular Biology La Conception Hospital Marseille France
12. Clinique Dermatologique Hôpital Civil, Hôpitaux Universitaires, Université de Strasbourg Strasbourg France
13. Department of Pathology Hospital Saint‐Louis, AP‐HP, Université Paris Cité, INSERM U976 Paris France
14. Department of Pathology APHM, Timone University Hospital Marseille France