{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T18:44:27Z","timestamp":1788461067290,"version":"build-2803163510"},"reference-count":46,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"2","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2023,2]]},"abstract":"<jats:p>Solitary fibrous tumors (SFTs) are ubiquitous soft tissue neoplasms known for their protean histology and potentially aggressive behavior. Although most cases are composed of a monotonous proliferation of spindle cells, some tumors show unusual cytologic features. We have studied 13 SFTs that were characterized by a predominant population of round epithelioid cells with abundant eosinophilic cytoplasm and clear cell changes. The tumors occurred in 8 women and 5 men, aged 36 to 80 years (mean=63\u00a0y), and were located within the orbit (3), lower extremity (3), retroperitoneum (2), abdominal cavity (2), and superficial soft tissues of the neck, pelvis, and pubis (1 each). The tumors measured from 3.5 to 24.5\u00a0cm. Using a risk assessment system, 6 cases were stratified as low-risk tumors; 3 of these showed no evidence of recurrence or metastases from 6 to 18 years, and 1 tumor in the orbit recurred and led to the patient\u2019s demise. Five cases were of intermediate risk; clinical follow-up showed no evidence of recurrence or metastases from 3 to 4 years in 3 patients, and 1 patient suffered a recurrence 4 years after diagnosis. Two cases were high risk; 1 patient died after 1 year and the second patient experienced local recurrence at 4 years. Immunohistochemical studies showed nuclear positivity for STAT6 in 10 cases. CD34 immunohistochemistry was positive in 11 cases. A <jats:italic toggle=\"yes\">NAB2::STAT6<\/jats:italic> rearrangement was present in all cases. Epithelioid and clear cell SFT should be considered in the differential diagnosis of soft tissue neoplasms with epithelioid and clear cell morphology.<\/jats:p>","DOI":"10.1097\/pas.0000000000001983","type":"journal-article","created":{"date-parts":[[2022,10,18]],"date-time":"2022-10-18T04:02:31Z","timestamp":1666065751000},"page":"259-269","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":11,"title":["Epithelioid and Clear Cell Solitary Fibrous Tumors"],"prefix":"10.1097","volume":"47","author":[{"given":"David I.","family":"Suster","sequence":"first","affiliation":[{"name":"Department of Pathology, Rutgers University New Jersey Medical School, Newark, NJ"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander C.","family":"Mackinnon","sequence":"additional","affiliation":[{"name":"The University of Alabama, Birmingham, AL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haider A.","family":"Mejbel","sequence":"additional","affiliation":[{"name":"The University of Alabama, Birmingham, AL"},{"name":"Emory University School of Medicine, Atlanta, GA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John M.","family":"Gross","sequence":"additional","affiliation":[{"name":"The Johns Hopkins University School of Medicine, Baltimore, MD"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saul","family":"Suster","sequence":"additional","affiliation":[{"name":"The Medical College of Wisconsin, Milwaukee, WI"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2022,10,18]]},"reference":[{"key":"R2-20250608","first-page":"169","article-title":"The spectrum of histologic growth patterns in benign and malignant fibrous tumors of the pleura","volume":"9","author":"Moran","year":"1992","journal-title":"Semin Diagn Pathol"},{"key":"R3-20250608","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1186\/s13000-021-01095-2","article-title":"The many faces of solitary fibrous tumor: diversity of histological features, differential diagnosis and role of molecular studies and surrogate markers in avoiding misdiagnosis and predicting the behavior","volume":"16","author":"Tariq","year":"2021","journal-title":"Diagn Pathol"},{"key":"R4-20250608","doi-asserted-by":"crossref","first-page":"1433","DOI":"10.1038\/modpathol.2017.54","article-title":"Risk assessment in solitary fibrous tumors: validation and refinement of a risk stratification model","volume":"30","author":"Demicco","year":"2017","journal-title":"Mod Pathol"},{"key":"R5-20250608","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1097\/PAS.0b013e31826a92f5","article-title":"Intrapulmonary solitary fibrous tumors: clinicopathologic and immunohistochemical study of 24 cases","volume":"37","author":"Rao","year":"2013","journal-title":"Am J Surg Pathol"},{"key":"R6-20250608","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1097\/00000478-198504000-00001","article-title":"Epithelioid sarcoma. 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