{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:54:51Z","timestamp":1760147691821,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T00:00:00Z","timestamp":1677196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cancers"],"abstract":"<jats:p>Histology has not been accepted as a valid predictor of the biological behavior of extra-meningeal solitary fibrous tumors (SFTs). Based on the lack of a histologic grading system, a risk stratification model is accepted by the WHO to predict the risk of metastasis; however, the model shows some limitations to predict the aggressive behavior of a low-risk\/benign-appearing tumor. We conducted a retrospective study based on medical records of 51 primary extra-meningeal SFT patients treated surgically with a median follow-up of 60 months. Tumor size (p = 0.001), mitotic activity (p = 0.003), and cellular variants (p = 0.001) were statistically associated with the development of distant metastases. In cox regression analysis for metastasis outcome, a one-centimeter increment in tumor size enhanced the expected metastasis hazard by 21% during the follow-up time (HR = 1.21, CI 95% (1.08\u20131.35)), and each increase in the number of mitotic figures escalated the expected hazard of metastasis by 20% (HR = 1.2, CI 95% (1.06\u20131.34)). Recurrent SFTs presented with higher mitotic activity and increased the likelihood of distant metastasis (p = 0.003, HR = 12.68, CI 95% (2.31\u201369.5)). All SFTs with focal dedifferentiation developed metastases during follow-up. Our findings also revealed that assembling risk models based on a diagnostic biopsy underestimated the probability of developing metastasis in extra-meningeal SFTs.<\/jats:p>","DOI":"10.3390\/cancers15051441","type":"journal-article","created":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T03:01:01Z","timestamp":1677207661000},"page":"1441","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Value of Cellular Components and Focal Dedifferentiation to Predict the Risk of Metastasis in a Benign-Appearing Extra-Meningeal Solitary Fibrous Tumor: An Original Series from a Tertiary Sarcoma Center"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9564-9627","authenticated-orcid":false,"given":"Mohammad","family":"Hassani","sequence":"first","affiliation":[{"name":"Division of Orthopedic Surgery, McGill University Health Centre, Montreal, QC H3G 1A4, Canada"},{"name":"Department of Orthopedic Surgery, Mashhad University of Medical Sciences, Mashhad 91886-17871, Iran"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sungmi","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Pathology, McGill University Health Centre, Montreal, QC H4A 3J1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9649-7933","authenticated-orcid":false,"given":"Elaheh","family":"Ghodsi","sequence":"additional","affiliation":[{"name":"School of Public Health, University of Montreal, Montreal, QC H3N 1X9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leila","family":"Seddigh","sequence":"additional","affiliation":[{"name":"Department of Community Medicine, Tehran University of Medical Sciences, Tehran 14117-13135, Iran"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paul","family":"Kooner","sequence":"additional","affiliation":[{"name":"Division of Orthopedic Surgery, McGill University Health Centre, Montreal, QC H3G 1A4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ahmed","family":"Aoude","sequence":"additional","affiliation":[{"name":"Division of Orthopedic Surgery, McGill University Health Centre, Montreal, QC H3G 1A4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert","family":"Turcotte","sequence":"additional","affiliation":[{"name":"Division of Orthopedic Surgery, McGill University Health Centre, Montreal, QC H3G 1A4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"390","DOI":"10.1038\/modpathol.2013.164","article-title":"Nuclear expression of STAT6 distinguishes solitary fibrous tumor from histologic mimics","volume":"27","author":"Doyle","year":"2014","journal-title":"Mod. 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