Extraordinary Case ReportAngiomatoid Fibrous Histiocytoma With ALK Expression in an Unusual Location and Age GroupDe Noon, Solange MD*; Fleming, Andrew MBChB, FRCS, FCS, Plast BAPS, BAPRAS†; Singh, Manuraj MBBS Hons, MRCP, PhD, DipRCPath‡ Author Information *Department of Histopathology, Department of Cellular Pathology, St George's University Hospital, London, United Kingdom; and Departments of †Plastic Surgery, and ‡Cellular Pathology, St George's University Hospital, London, United Kingdom. Correspondence: Solange De Noon, MD, Department of Cellular Pathology, St George's University Hospital, Blackshaw Road, Tooting, London SW17 0QT (e-mail: [email protected]). The authors declare no conflicts of interest. The American Journal of Dermatopathology: September 2020 - Volume 42 - Issue 9 - p 689-693 doi: 10.1097/DAD.0000000000001649 Buy Metrics Abstract Angiomatoid fibrous histiocytoma (AFH) is a relatively rare soft tissue tumor of intermediate malignant potential, occurring most commonly in young adults, with a recognized propensity for local recurrence and occasional metastasis. A case of AFH occurring on the finger of a 60-year-old man is described in which the unusual location and age group for this entity raised the original wrong diagnosis of an aneurysmal and cellular fibrous histiocytoma. Further workup demonstrated an EWSR1-CREB1 translocation, confirming the correct diagnosis of AFH. Strong anaplastic lymphoma kinase (ALK) expression using the antibody clone D5F3 was demonstrated in our case on immunohistochemistry, which is in concordance with recent findings of anaplastic lymphoma kinase positivity with this antibody in the majority of AFHs. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.