{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,25]],"date-time":"2025-11-25T07:23:37Z","timestamp":1764055417232,"version":"3.45.0"},"reference-count":15,"publisher":"Springer Science and Business Media LLC","issue":"5","license":[{"start":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:00:00Z","timestamp":1760140800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:00:00Z","timestamp":1760140800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100006447","name":"University of Zurich","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100006447","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Virchows Arch"],"published-print":{"date-parts":[[2025,11]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Diagnosing undifferentiated spindle cell and pleomorphic tumours of the sun-exposed skin of elderly patients is common and challenging. This paper presents the case of a 64-year-old man with a tumour that was initially diagnosed as an atypical fibroxanthoma, but which metastasised to the bone and lung, resulting in death within two years. Extensive comparative molecular studies were performed using next-generation sequencing (NGS) and methylomic analysis, which demonstrated that the skin tumour and the bone metastases corresponded to the same neoplasms. In addition to other aberrations, NGS analysis of both tumour manifestations revealed\n                    <jats:italic>NF1<\/jats:italic>\n                    gene mutations, suggesting a diagnosis of undifferentiated melanoma. Interestingly, however, the methylomic analysis grouped the tumours with the \u201catypical fibroxanthoma\/pleomorphic dermal sarcoma (AFX\/PDS)\u201d class of the reference cases, rather than with conventional or desmoplastic melanomas. Molecular studies may help to reveal the genetic basis of difficult-to-classify undifferentiated skin neoplasms as well as help to estimate their biological potential.\n                  <\/jats:p>","DOI":"10.1007\/s00428-025-04265-5","type":"journal-article","created":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:18:02Z","timestamp":1760145482000},"page":"1173-1178","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Undifferentiated melanoma: a molecular study of a fatal metastatic \u201catypical fibroxanthoma (AFX)\u201d"],"prefix":"10.1007","volume":"487","author":[{"given":"Simon","family":"Haefliger","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Baptiste","family":"Ameline","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Veronika","family":"Blum","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matthias S.","family":"Matter","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3329-4186","authenticated-orcid":false,"given":"Beata","family":"Bode-Lesniewska","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2025,10,11]]},"reference":[{"key":"4265_CR1","doi-asserted-by":"publisher","first-page":"306","DOI":"10.1053\/j.semdp.2023.06.001","volume":"40","author":"A Agaimy","year":"2023","unstructured":"Agaimy A (2023) The many faces of atypical fibroxanthoma. Semin Diagn Pathol 40:306\u2013312. https:\/\/doi.org\/10.1053\/j.semdp.2023.06.001","journal-title":"Semin Diagn Pathol"},{"key":"4265_CR2","doi-asserted-by":"publisher","first-page":"240","DOI":"10.1097\/PAS.0000000000001645","volume":"45","author":"A Agaimy","year":"2021","unstructured":"Agaimy A, Stoehr R, Hornung A, Popp J, Erdmann M, Heinzerling L, Hartmann A (2021) Dedifferentiated and undifferentiated melanomas: report of 35 new cases with literature review and proposal of diagnostic criteria. 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International Agency for Research on Cancer, Lyon (France)"},{"key":"4265_CR7","doi-asserted-by":"publisher","first-page":"2009","DOI":"10.1038\/s41379-021-00857-z","volume":"34","author":"I Ferreira","year":"2021","unstructured":"Ferreira I, Droop A, Edwards O, Wong K, Harle V, Habeeb O, Gharpuray-Pandit D, Houghton J, Wiedemeyer K, Mentzel T, Billings SD, Ko JS, Fuzesi L, Mulholland K, Prusac IK, Liegl-Atzwanger B, de Saint Aubain N, Caldwell H, Riva L, van der Weyden L, Arends MJ, Brenn T, Adams DJ (2021) The clinicopathologic spectrum and genomic landscape of de-\/trans-differentiated melanoma. 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Mod Pathol 31:418\u2013428. https:\/\/doi.org\/10.1038\/modpathol.2017.146","journal-title":"Mod Pathol"},{"key":"4265_CR9","doi-asserted-by":"publisher","first-page":"7","DOI":"10.1016\/j.ejca.2023.03.032","volume":"187","author":"J Hench","year":"2023","unstructured":"Hench J, Mihic-Probst D, Agaimy A, Frank S, Meyer P, Hultschig C, Simi S, Alos L, Balamurugan T, Blokx W, Bosisio F, Cappellesso R, Griewank K, Hadaschik E, van Kempen LC, Kempf W, Lentini M, Mazzucchelli L, Rinaldi G, Rutkowski P, Schadendorf D, Schilling B, Szumera-Cieckiewicz A, van den Oord J, Mandala M, Massi D, Group EM (2023) Clinical, histopathological and molecular features of dedifferentiated melanomas: an EORTC melanoma group retrospective analysis. 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Nat Commun 12:498. https:\/\/doi.org\/10.1038\/s41467-020-20603-4","journal-title":"Nat Commun"},{"key":"4265_CR11","doi-asserted-by":"publisher","DOI":"10.1186\/s13569-019-0113-6","volume":"9","author":"C Koelsche","year":"2019","unstructured":"Koelsche C, Stichel D, Griewank KG, Schrimpf D, Reuss DE, Bewerunge-Hudler M, Vokuhl C, Dinjens WNM, Petersen I, Mittelbronn M, Cuevas-Bourdier A, Buslei R, Pfister SM, Flucke U, Mechtersheimer G, Mentzel T, von Deimling A (2019) Genome-wide methylation profiling and copy number analysis in atypical fibroxanthomas and pleomorphic dermal sarcomas indicate a similar molecular phenotype. Clin Sarcoma Res 9:2. https:\/\/doi.org\/10.1186\/s13569-019-0113-6","journal-title":"Clin Sarcoma Res"},{"key":"4265_CR12","unstructured":"Mentzel TDW, Brenn T (2020) Atypica fibroxanthoma. In: Fletcher CDM (ed) WHO Classification of Tumours Editorial Board. Soft tissue and bone tumours [Internet]. 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Otherwise, the authors have no conflicts of interest to declare.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}}]}}