{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T13:49:37Z","timestamp":1785764977659,"version":"3.56.0"},"reference-count":31,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,8,2]],"date-time":"2026-08-02T00:00:00Z","timestamp":1785628800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Assistant Publique H\u00f4pitaux de Marseille"},{"id":[{"id":"https:\/\/ror.org\/002cp4060","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>Amplification of MDM2 is the molecular hallmark of atypical lipomatous tumor\/well-differentiated liposarcoma (ALT\/WDL) and dedifferentiated liposarcoma (DDL). While fluorescence in situ hybridization (FISH) is widely used for diagnosis, the diagnostic and prognostic value of droplet digital PCR (ddPCR) remains poorly defined. We retrospectively analyzed 341 primary adipocytic tumors, including 85 liposarcomas (22 DDL), using ddPCR to quantify MDM2 copy number variation (CNV). Diagnostic performance was compared with FISH, and associations with clinicopathological variables and outcomes were evaluated using non-parametric tests, ROC analysis, survival analysis, and Firth\u2019s penalized Cox models. Comparison with FISH confirmed the diagnostic utility of ddPCR for detecting MDM2 amplification, while quantitative CNV assessment provided additional prognostic information. CNV values were significantly higher in deep-seated and dedifferentiated tumors and were strongly associated with local recurrence. ROC analysis identified a threshold of 16.85 copies predicting both dedifferentiation and recurrence (AUC 0.982 and 0.942, respectively). Patients with CNV \u2265 16.85 copies had significantly shorter recurrence-free and overall survival. In multivariable analysis, high CNV remained an independent predictor of recurrence (HR 36.6, 95% CI 4.0\u20134914.2). These findings support ddPCR as a robust method for MDM2 assessment and suggest that quantitative MDM2 copy number may improve both diagnosis and risk stratification in liposarcoma.<\/jats:p>","DOI":"10.3390\/ijms27156932","type":"journal-article","created":{"date-parts":[[2026,8,3]],"date-time":"2026-08-03T12:57:56Z","timestamp":1785761876000},"page":"6932","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Droplet Digital PCR Assessment of MDM2 Amplification in Liposarcoma Diagnosis and Prognosis: A French Single-Center Cohort Study"],"prefix":"10.3390","volume":"27","author":[{"given":"Amira","family":"Amri","sequence":"first","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aur\u00e9lie","family":"Haffner","sequence":"additional","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fr\u00e9deric","family":"Fina","sequence":"additional","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4545-6063","authenticated-orcid":false,"given":"Romain","family":"Appay","sequence":"additional","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florence","family":"Duffaud","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, La Timone University Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S\u00e9bastien","family":"Salas","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, La Timone University Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean-Camille","family":"Matt\u00e9i","sequence":"additional","affiliation":[{"name":"Orthopedic and Traumatologic Surgery Department, North Hospital, La Conception Hospital, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandre","family":"Rochwerger","sequence":"additional","affiliation":[{"name":"Orthopedic and Traumatologic Surgery Department, North Hospital, La Conception Hospital, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4715-6243","authenticated-orcid":false,"given":"Christophe","family":"Chagnaud","sequence":"additional","affiliation":[{"name":"Department of Radiology, La Conception University Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R\u00e9mi","family":"Fernandez","sequence":"additional","affiliation":[{"name":"Department of Radiology, La Conception University Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9 Maues de","family":"Paula","sequence":"additional","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierre-Alexandre","family":"Just","sequence":"additional","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0496-458X","authenticated-orcid":false,"given":"Ilyes","family":"Hamouda","sequence":"additional","affiliation":[{"name":"EA 3279, CEReSS, Research Centre on Health Services and Quality of Life, Aix Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shani","family":"Diai","sequence":"additional","affiliation":[{"name":"EA 3279, CEReSS, Research Centre on Health Services and Quality of Life, Aix Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chelsea Anjuly","family":"Neda","sequence":"additional","affiliation":[{"name":"Cell Biology Department, Timone Hospital, Institut National de la Sant\u00e9 et de la Recherche M\u00e9dicale (INSERM), Marseille Medical Genetics (MMG), Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0045-5641","authenticated-orcid":false,"given":"Patrice","family":"Roll","sequence":"additional","affiliation":[{"name":"Cell Biology Department, Timone Hospital, Institut National de la Sant\u00e9 et de la Recherche M\u00e9dicale (INSERM), Marseille Medical Genetics (MMG), Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0458-5109","authenticated-orcid":false,"given":"Elise","family":"Kaspi","sequence":"additional","affiliation":[{"name":"Cell Biology Department, Timone Hospital, Institut National de la Sant\u00e9 et de la Recherche M\u00e9dicale (INSERM), Marseille Medical Genetics (MMG), Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine","family":"Gallardo","sequence":"additional","affiliation":[{"name":"M2GM, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne","family":"Barlier","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular Biology GEnOP\u00e9, BIOGENOPOLE, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Institut National de la Sant\u00e9 et de la Recherche M\u00e9dicale (INSERM), Marseille Medical Genetics (MMG), MarMaRa Institute, La Timone University Hospital, Aix Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Corinne","family":"Bouvier","sequence":"additional","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3321-6951","authenticated-orcid":false,"given":"Diane","family":"Frankel","sequence":"additional","affiliation":[{"name":"Cell Biology Department, Timone Hospital, Institut National de la Sant\u00e9 et de la Recherche M\u00e9dicale (INSERM), Marseille Medical Genetics (MMG), Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicolas","family":"Macagno","sequence":"additional","affiliation":[{"name":"Department of Pathology and Neuropathology, Timone Hospital, Assistance Publique\u2013H\u00f4pitaux de Marseille (AP-HM), Aix-Marseille University, 13005 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ducimeti\u00e8re, F., Lurkin, A., Ranch\u00e8re-Vince, D., Decouvelaere, A.V., P\u00e9oc\u2019h, M., Istier, L., Chalabreysse, P., Muller, C., Alberti, L., and Bringuier, P.-P. 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