Stratigos, Alexander J, Garbe, Claus, Dessinioti, Clio, Lebbe, Celeste, Bataille, Veronique, Bastholt, Lars, Dreno, Brigitte, Fargnoli, Maria Concetta, Forsea, Ana Maria, Frenard, Cecille, Harwood, Catherine Α, Hauschild, Axel, Hoeller, Christoph, Kandolf-Sekulovic, Lidija, Kaufmann, R, Kelleners-Smeets, Nicole Wj, Malvehy, Josep, Del Marmol, Veronique, Middleton, Mark R, Moreno-Ramirez, David, Pellecani, Giovanni, Peris, Ketty, Saiag, Philippe, van den Beuken-van Everdingen, Marieke H J, Vieira, Ricardo, Zalaudek, Iris, Eggermont, Alexander M M, Grob, Jean-Jacques, European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO) and the European Organization for Research and Treatment of Cancer (EORTC), National and Kapodistrian University of Athens (NKUA), Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, Immunologie humaine, physiopathologie & immunothérapie (HIPI (UMR_S_976 / U976)), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Cité (UPCité), North & East Hertfordshire NHS Trust [Northwood, UK], Odense University Hospital (OUH), Centre de Recherche en Cancérologie et Immunologie Nantes-Angers (CRCINA), Université d'Angers (UA)-Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre hospitalier universitaire de Nantes (CHU Nantes), Centre d’Investigation Clinique de Nantes (CIC Nantes), Université de Nantes (UN)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre hospitalier universitaire de Nantes (CHU Nantes), University of L'Aquila [Italy] (UNIVAQ), University of Medicine and Pharmacy 'Carol Davila' Bucharest (UMPCD), Queen Mary University of London (QMUL), Kiel University, Medizinische Universität Wien = Medical University of Vienna, Military Medical Academy [Belgrade, Serbia] (2MA), Frankfurt University Hospital, Maastricht University Medical Centre (MUMC), Maastricht University [Maastricht], University of Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona (UB), CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III [Madrid] (ISC), Université libre de Bruxelles (ULB), Hôpital Erasme [Bruxelles], University of Oxford, Hospital Universitario Virgen Macarena [Sevilla, Spain] (HUVM), University - Hospital of Modena and Reggio Emilia [Modena, Italy], Università cattolica del Sacro Cuore = Catholic University of the Sacred Heart [Roma] (Unicatt), Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Istituto Neurologico Mediterraneo (NEUROMED I.R.C.C.S.), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)-University of Naples Federico II = Università degli studi di Napoli Federico II, Biomarqueurs et essais cliniques en Cancérologie et Onco-Hématologie (BECCOH), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Paris-Saclay, Hôpital Ambroise Paré [AP-HP], University Veterinary Hospital [Coimbra, Portugal], Università degli studi di Trieste = University of Trieste, Princess Máxima Center for Pediatric Oncology, Assistance Publique - Hôpitaux de Marseille (APHM), Aix Marseille Université (AMU), Novartis Les Laboratories Pierre Fabre Sanofi Bristol-Myers Squibb, BMS Pfizer Amgen Roche LEO Pharma Research Foundation Cilag Merck Meso Scale Diagnostics, MSD Genentech, The guidelines were supported by grants from the EADO for the guideline meetings. The authors did this work on a voluntary basis and did not receive any honorarium or reimbursements. Guidelines development group members stated their conflicts of interest in the relevant section., Dr. Stratigos reports personal fees and/or research support from Novartis , Roche , BMS , Abbvie , Sanofi , Regeneron , Genesis Pharma , outside the submitted work. Dr. Garbe reports personal fees from Amgen , personal fees from MSD , grants and personal fees from Novartis , grants and personal fees from NeraCare, grants and personal fees from BMS , personal fees from Pierre Fabre , personal fees from Philogen, grants and personal fees from Roche , grants and personal fees from Sanofi , outside the submitted work. Dr. Dessinioti has nothing to disclose. Dr. Lebbe reports grants and personal fees from Bristol-Myers Squibb , personal fees from MSD , personal fees from Novartis , personal fees from Amgen , grants and personal fees from Roche , personal fees from Avantis Medical Systems, personal fees from Pierre Fabre , personal fees from Pfizer , personal fees from Incyte, outside the submitted work. Dr. Bataille reports personal fees from Novartis , personal fees from Merck MSD , outside the submitted work. Dr. Bastholt reports personal fees for advisory board activity: BMS , Roche , Novartis , Pierre-Fabre, Astra Zeneca, InCyte, MSD / Merck , Bayer . Dr. Dréno reports grants and personal fees from BMS , personal fees from MSD , grants and personal fees from Roche , grants and personal fees from Fabre, grants and personal fees from Sanofi , outside the submitted work. Dr. Fargnoli reports grants and personal fees from Almirall, grants and personal fees from Leo Pharma, personal fees from Janssen, grants and personal fees from Novartis , personal fees from Lilly , grants and personal fees from Sanofi , personal fees from UCB , grants and personal fees from Abbvie , personal fees from Celgene , personal fees from Pierre Fabre , grants and personal fees from Galderma , personal fees from Mylan, personal fees from Medac Pharma, personal fees from Roche , personal fees from Sun Pharma , outside the submitted work. Dr. Forsea reports scientific consultant/speaker fee from Novartis , Leo Pharma, Solartium, Pierre-Fabre, outside the submitted work. Dr. Frenard has nothing to disclose. Dr. Harwood reports institutional research grants and honoraria from Sanofi , Novartis , Merck , Pfizer , Galderma , MEDA, Almirall, Pellepharm, Leo Pharma, CERIES. Dr. Hauschild reports honoraria and/or research grants from: Almirall, BMS , Roche , Novartis , Pierre-Fabre, Sunpharma, MerckSerono, SanofiAventis, Regeneron , MSD / Merck , Philogen, OncoSec outside the submitted work. Dr. Hoeller reports grants and personal fees from Amgen , personal fees from BMS , personal fees from MSD , personal fees from Novartis , personal fees from Pierre Fabre , personal fees from Roche , personal fees from Sanofi , personal fees from Incyte, outside the submitted work. Dr. Kandolf-Sekulovic reports speakers’ honoraria for Roche, Novartis, MSD, BMS, Janssen outside the submitted work. Dr. Kaufmann reports institutional research grants (clinical trials) from: AbbVie , Amgen , Biontech, BMS , Celgene , Galderma , Janssen, Leo, Lilly , Merck , MSD , Novartis , Pierre Fabre , Pfizer , Regeneron , Roche , Wyeth . Advisory Board and Honoraria from Merz, Roche, Novartis. Dr. Kelleners-Smeets reports grants from Netherlands Organization for Health Research and Development, other from Janssen-Cilag, other from AbbVie , other from Galderma , outside the submitted work. Dr. Malvehy reports research grants from Almirall, ISDIN, Leo Pharma, Galderma , GSK , Cantabria, participation in advisory board meetings for Almirall, Sunpharma, BMS , Roche , Novartis , Pierre-Fabre. Dr. del Marmol reports personal fees from MSD , from BMS , personal fees from Sanofi , grants and personal fees from ABVIE, grants from Jansen, outside the submitted work. Dr. Middleton reports personal fees and/or grants from Amgen , Roche , Astrazeneca, GSK , Novartis , Immunocore, BMS , Eisai and Merck . Institutional funding from Millennium, Vertex, Pfizer , Regeneron , TCBiopharma, BiolineRx, Replimune, outside the submitted work. Dr. Moreno-Ramírez has nothing to disclose. Dr. Pellecani reports grants from university of modena and reggio emilia, during the conduct of the study, grants from novartis, grants and personal fees from almirall, grants from leo pharma, from null, outside the submitted work. Dr. Peris reports honoraria for advisory board and grants from AbbVie , Almirall, Biogen Celgene , Lilly , Galderma , Leo Pharma, Novartis , Roche , Sanofi , Sun Pharma , Sandoz outside the submitted work. Dr. Saiag reports honoraria for advisory board and grants from Amgen , Bristol-Myers Squibb , MSD , Merck-Serono, Novartis , Pfizer , Roche- Genentech , Pierre Fabre , and Sanofi , outside the submitted work. Dr. van den Beuken-van Everdingen has nothing to disclose. Dr. Vieira has nothing to disclose. Dr. Zalaudek reports honoraria and advisory board and grants from Sanofi , Sun Pharma , Novartis , Galderma , Roche , Celgene , Almirall, Leofarma, Mylan, Difa Cooper, Cieffe Labs, La Roche Posay, Pierre Fabre . Dr. Eggermont reports over the last 5 years personal fees as a consultant advisor for Biocad, BioInvent, Bristol Myers Squibb ( BMS ), CatalYm, Ellipses, Glaxo Smith Kline ( GSK ), HalioDX, Incyte, IO Biotech, ISA Pharmaceuticals, Merck Sharpe & Dohme ( MSD ), Novartis , Pfizer , Polynoma, Regeneron , Sanofi , Sellas, SkylineDx. Dr. Grob reports personal fees for advisory board and as speaker from Amgen , Roche , GSK , Novartis , BMS , Pierre fabre, Merck , Sanofi , Merck , Pfizer outside the submitted work., European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO) and the European Organization for Research and Treatment of Cancer (EORTC), HAL UVSQ, Équipe, Dermatologie, MUMC+: MA Dermatologie (9), RS: GROW - R3 - Innovative Cancer Diagnostics & Therapy, RS: MHeNs - R3 - Neuroscience, MUMC+: TPZ Palliatieve Zorg (9), Stratigos, A. J., Garbe, C., Dessinioti, C., Lebbe, C., Bataille, V., Bastholt, L., Dreno, B., Fargnoli, M. C., Forsea, A. M., Frenard, C., Harwood, C. Alpha., Hauschild, A., Hoeller, C., Kandolf-Sekulovic, L., Kaufmann, R., Kelleners-Smeets, N. W., Malvehy, J., del Marmol, V., Middleton, M. R., Moreno-Ramirez, D., Pellecani, G., Peris, K., Saiag, P., van den Beuken-van Everdingen, M. H. J., Vieira, R., Zalaudek, I., Eggermont, A. M. M., Grob, J. -J., Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Paris (UP), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Nantes - UFR de Médecine et des Techniques Médicales (UFR MEDECINE), and Université de Nantes (UN)-Université de Nantes (UN)-Centre hospitalier universitaire de Nantes (CHU Nantes)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA)