{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,8]],"date-time":"2025-12-08T22:47:06Z","timestamp":1765234026976,"version":"3.43.0"},"reference-count":19,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T00:00:00Z","timestamp":1754870400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"<jats:p>We present a rare case of dedifferentiated adamantinoma. The 48-year-old male patient was initially diagnosed with classic adamantinoma in the right fibula and underwent curettage. Two years postoperatively, the patient presented with progressive swelling and pain in the same region. Imaging disclosed an expansile lesion with mixed lytic and sclerotic changes involving the medulla and adjacent soft tissue. A biopsy was performed, and a diagnosis of classic adamantinoma was made. Considering the significant clinical symptoms and imaging features, a below-knee amputation was performed. Histologically, the tumor exhibited two distinct patterns: classic adamantinoma juxtaposed to a dedifferentiated component, characterized by chondrosarcomatous areas with moderate cellularity and abundant hyaline cartilage matrix. Myxoid areas containing malignant cartilage cells of myxoid chondrosarcoma were also observed. Immunohistochemically, the dedifferentiated areas showed complete loss of epithelial markers. At a two-year follow-up, the patient remains free of recurrence or metastasis. Dedifferentiated adamantinoma is an exceedingly rare primary bone tumor malignancy lacking specific clinical manifestations. In our case, the initial biopsy specimen revealed only epithelial cells, leading to an underdiagnosis of classic adamantinoma until further sampling revealed the dedifferentiated component. It underscores the importance of thorough sampling, close radiologic-pathologic correlation, and a multidisciplinary framework for accurate diagnosis and optimal management of complex bone tumors. Early recognition of the dedifferentiated features can guide appropriate surgical management and improve patient outcomes.<\/jats:p>","DOI":"10.3389\/fonc.2025.1559965","type":"journal-article","created":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T04:10:57Z","timestamp":1754885457000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Dedifferentiated adamantinoma of long bones: a case report and literature review"],"prefix":"10.3389","volume":"15","author":[{"given":"Xiaofei","family":"Xiu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiajia","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lisha","family":"Duan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaomei","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zinan","family":"Guo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xuelan","family":"Xiao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qianhui","family":"Han","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Feng","family":"Gao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2025,8,11]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jbo.2023.100489","article-title":"Adamantinoma: A review of the current literature","volume":"41","author":"Smyth","year":"2023","journal-title":"J Bone Oncol"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.21873\/invivo.12600","article-title":"Adamantinoma: an updated review","volume":"35","author":"Varvarousis","year":"2021","journal-title":"In Vivo"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1186\/1746-1596-3-8","article-title":"Adamantinoma: a clinicopathological review and update","volume":"3","author":"Jain","year":"2008","journal-title":"Diagn Pathol"},{"key":"B4","doi-asserted-by":"publisher","first-page":"23","DOI":"10.3109\/01913123.2011.631725","article-title":"Mesenchymal-epithelial differentiation of adamantinoma of long bones: an immunohistochemical and ultrastructural study","volume":"36","author":"Sarita-Reyes","year":"2012","journal-title":"Ultrastruct Pathol"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1097\/00000478-200312000-00005","article-title":"Dedifferentiated adamantinoma with revertant mesenchymal phenotype","volume":"27","author":"Hazelbag","year":"2003","journal-title":"Am J Surg Pathol"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1097\/PAP.0000000000000293","article-title":"The 2020 WHO classification of tumors of bone: an updated review","volume":"28","author":"Choi","year":"2021","journal-title":"Adv Anat Pathol"},{"key":"B7","doi-asserted-by":"publisher","first-page":"193","DOI":"10.1177\/1066896918790388","article-title":"Clinicopathologic features of two rare cases of dedifferentiated adamantinomas, including diagnostic implications","volume":"27","author":"Rekhi","year":"2019","journal-title":"Int J Surg Pathol"},{"key":"B8","article-title":"Dedifferentiated adamantinoma: clinic-pathological and molecular study on four cases","author":"Tirabosco","year":"2015"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1097\/PAS.0b013e3181ecfe6a","article-title":"Dedifferentiated classic adamantinoma of the tibia: a report of a case with eventual complete revertant mesenchymal phenotype","volume":"34","author":"Izquierdo","year":"2010","journal-title":"Am J Surg Pathol"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1016\/j.otsr.2011.05.005","article-title":"Dedifferentiated adamantinoma associated with fibrous dysplasia","volume":"97","author":"Nouri","year":"2011","journal-title":"Orthop Traumatol Surg Res"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.3760\/cma.j.cn112151-20211028-00784","article-title":"Dedifferentiatd adamantinoma: report of a case","volume":"51","author":"Dong","year":"2022","journal-title":"Zhonghua Bing Li Xue Za Zhi"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1016\/j.path.2021.06.012","article-title":"Osteofibrous dysplasia and adamantinoma","volume":"14","author":"Nascimento","year":"2021","journal-title":"Surg Pathol Clin"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1007\/s00428-011-1081-2","article-title":"Podoplanin expression in adamantinoma of long bones and osteofibrous dysplasia","volume":"459","author":"Kashima","year":"2011","journal-title":"Virchows Arch"},{"key":"B14","article-title":"DNA aberrations in the epithelial cell component of adamantinoma of long bones","volume":"147","author":"Hazelbag","year":"1995","journal-title":"Am J Pathol"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1016\/j.modpat.2023.100301","article-title":"DNA methylation profiling distinguishes adamantinoma-like Ewing sarcoma from conventional Ewing sarcoma","volume":"36","author":"Fritchie","year":"2023","journal-title":"Mod Pathol"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1038\/s41379-018-0115-6","article-title":"Genetic and molecular reappraisal of spindle cell adamantinoma of bone reveals a small subset of misclassified intraosseous synovial sarcoma","volume":"32","author":"Horvai","year":"2019","journal-title":"Mod Pathol"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1155\/2016\/5982313","article-title":"A case of metastatic adamantinoma that responded well to Sunitinib","volume":"5982313","author":"Liman","year":"2016","journal-title":"Case Rep Oncol Med"},{"key":"B18","doi-asserted-by":"publisher","first-page":"2809647","DOI":"10.1155\/2020\/2809647","article-title":"Epidemiological study of adamantinoma from US Surveillance, Epidemiology, and End Results Program: III Retrospective Analysis","author":"Aytekin","year":"2020","journal-title":"J Onclo"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1016\/j.humpath.2024.02.001","article-title":"Dedifferentiation in bone and soft tissue sarcomas: How do we define it? What is prognostically relevant","volume":"147","author":"Dry","year":"2024","journal-title":"Hum Pathol"}],"container-title":["Frontiers in Oncology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2025.1559965\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,11]],"date-time":"2025-08-11T04:10:58Z","timestamp":1754885458000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2025.1559965\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,8,11]]},"references-count":19,"alternative-id":["10.3389\/fonc.2025.1559965"],"URL":"https:\/\/doi.org\/10.3389\/fonc.2025.1559965","relation":{},"ISSN":["2234-943X"],"issn-type":[{"value":"2234-943X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,8,11]]},"article-number":"1559965"}}