臨床特點(diǎn)：患者平均年齡45歲（10-87歲）,，男性略多見；腫瘤多發(fā)生于下肢深部軟組織和軀干,，偶可發(fā)生于盆腔和腎臟等部位,；常表現(xiàn)為緩慢增大腫塊，可有近期明顯增大伴疼痛,；

組織形態(tài)學(xué)：鏡下以大量玻璃樣變的膠原性間質(zhì)和其間夾雜呈條索狀,、巢狀或片狀排列的小至中等大的圓形、卵圓形或多邊形上皮樣瘤細(xì)胞為特征,；瘤細(xì)胞胞質(zhì)空而透亮或略嗜伊紅色,，核不規(guī)則或成角狀，核染色質(zhì)均勻,，可見小核仁，核異型性不明顯,，核分裂象少見,；部分腫瘤可見類似經(jīng)典纖維肉瘤成分，表現(xiàn)為細(xì)胞密度增生，核異型性顯著,，并可見較多核分裂象,。少數(shù)病例腫瘤部分區(qū)域還可與其他類型的硬化性纖維肉瘤如低度惡性纖維黏液樣肉瘤相重疊，稱為雜合性腫瘤,；甚至還可有非纖維化亞型出現(xiàn),；

Figure 6.70 Sclerosing Epithelioid Fibrosarcoma. Cords and trabeculae of epithelioid cells in a densely hyalinized stroma.

Figure 6.71 Sclerosing Epithelioid Fibrosarcoma. Bland uniform epithelioid cells have clear cytoplasm. The sclerotic stroma may mimic osteoid.

Figure 6.72 Sclerosing Epithelioid Fibrosarcoma. A fascicular, fibroblastic spindle cell component is sometimes also present.

免疫表型：特征性表達(dá)MUC4，可表達(dá)HMGA2和TLE1,可局灶或弱陽性表達(dá)EMA,、S100,、inhibin和IFITM1；可有MDM2過表達(dá),；不表達(dá)SOX10,、GFAP、keratin,、syn、SALL4,、cyclin D1,、Claudin-4、calretinin,、OCT3/4,、CD138、CD10,、CD34,、SMA、desmin,、STAT6,、P53、CD68,、HMB45和CD30,；

分子遺傳學(xué)：硬化性上皮樣纖維肉瘤與低度惡性纖維黏液樣肉瘤有一定的關(guān)系，不僅兩者均表達(dá)MUC4,，而且均存在FUS基因易位,。在純的硬化性上皮樣纖維肉瘤中90%病例顯示EWSR1（伙伴基因有：CREB3L1、CREB3L2和CREB3L3）基因易位,，少數(shù)為FUS基因易位,；雜合性硬化性上皮樣纖維肉瘤/低度惡性纖維黏液樣肉瘤多顯示為FUS-CREB3L2基因易位；低度惡性纖維黏液樣肉瘤多顯示為FUS-CREB3L2基因易位,，少數(shù)為FUS-CREB3L1和EWSR1-CREB3L1,；

鑒別診斷：根據(jù)不同部位,、不同年齡和不同的形態(tài)學(xué)表現(xiàn)，尤其是小標(biāo)本時(shí),，需與硬化性上皮樣纖維肉瘤的疾病包括孤立性纖維性腫瘤,、玻璃樣變纖維瘤病、浸潤(rùn)性或轉(zhuǎn)移性癌,、梭形細(xì)胞型滑膜肉瘤,、軟組織透明細(xì)胞肉瘤、上皮樣平滑肌肉瘤,、硬化性橫紋肌肉瘤等,；

參考文獻(xiàn)：

【1】Expanding the spectrum of translocations in sclerosing epitheloid fibrosarcoma: A new case with EWSR1-CREB3L3 fusion.2018.

【2】A rare case of TLE1-positive sclerosing epithelioid fibrosarcoma expanding the differential diagnosis of TLE1-positive tumors: a case report.2019.

【3】Primary sclerosing epithelioid fibrosarcoma of the kidney: Report of two additional cases with a clinicopathological and molecular cytogenetic study.2019.

【4】Primary Renal Hybrid Low-grade Fibromyxoid Sarcoma-Sclerosing Epithelioid Fibrosarcoma: An Unusual Pediatric Case With EWSR1-CREB3L1 Fusion.2018.

【5】A genetic dichotomy between pure sclerosing epithelioid fibrosarcoma (SEF) and hybrid SEF/low-grade fibromyxoid sarcoma: a pathologic and molecular study of 18 cases.2015.

【6】Mesenchymal Tumors with EWSR1 Gene Rearrangements.2019.

【7】Practical Soft Tissue Pathology：A Diagnostic Approach. 2018.

【8】Non-fibrosing sclerosing epithelioid fibrosarcoma: an unusual variant.2016.

【9】FUS rearrangements are rare in pure sclerosing epithelioid fibrosarcoma. 2012.