Short Communications: Clinical ResearchClinical response under MEK inhibitor alone in metastatic melanoma with a novel fusion involving the RAF1 geneBoileau, Mariea,b,c; Descarpentries, Clotildeb,d; Delzenne, Guillaumea,c; Trentesaux, Victorinea; Greliak, Annaa,b; Jamme, Philippea,b; Marchetti, Philippeb,c,e; Mortier, Laurenta,b Author Information aDepartment of Dermatology, Service de Dermatologie, Hôpital C. Huriez, CHU de Lille bDepartment of Medicine, Université de Lille cUMR 1172 INSERM, Université de Lille dDepartment of Biochemistry and Molecular Biology ‘Hormonology Metabolism Nutrition Oncology’, CHU de Lille and eDepartment of Tissu Bank, Banque de tissus, Centre de biologie et pathologie, CHU de Lille, Lille, France Received 17 August 2022 Accepted 7 January 2023. Correspondence to Laurent Mortier, MD, PhD, Department of Dermatology, Hopital Claude Huriez, CHU of Lille, 2 rue Michel Polonowski 59000, France, Tel: +33 320 44 41 93; e-mail: [email protected] Melanoma Research 33(3):p 247-251, June 2023. | DOI: 10.1097/CMR.0000000000000882 Buy Metrics Abstract Currently, in the absence of BRAFV600 mutation, the management of advanced melanomas is based on immunotherapies, but only half of the patients are responders. RAF1 (also named CRAF) fusions occur in 1–2.1% of wild-type melanomas. Preclinical data suggest that the presence of RAF fusion may be sensitive to MEK inhibitors. We report the case of a patient with an advanced melanoma harboring an EFCC1–RAF1 fusion who showed a clinical benefit from and a partial response to a MEK inhibitor. Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.