硬化性上皮样纤维肉瘤的临床病理学观察

目的探讨硬化性上皮样纤维肉瘤的临床病理学特征、免疫表型及鉴别诊断.方法应用光镜和免疫组织化学LSAB法对8例硬化性上皮样纤维肉瘤进行临床病理学分析和免疫表型检测.结果患者均为成年人,男性5例,女性3例,年龄35～54岁(平均45岁).临床上表现为深部软组织内缓慢性生长的肿块,其中大腿/臀部3例,右上臂/肩部2例,胸壁和背部2例,小腿1例.大体上,肿块呈结节状,境界相对清楚,直径2.0～10.5 cm(平均6 em),切面呈灰白色,质地坚韧或有弹性.组织学上,肿瘤由形态一致、小至中等大的圆形或多边形上皮样细胞组成,多呈单个或狭窄的条索状排列,夹杂于大量嗜伊红色、玻璃样变的胶原纤维之间.部分区域中也可排列成巢状、片状或腺泡状.高倍镜下,瘤细胞的胞质透亮或嗜伊红色,核异型性不明显,核分裂象也少见(＜1/10HPF).另在2例肿瘤的局部区域,细胞密度明显增加,核有显著的异型性,核分裂象也易见,类似经典的纤维肉瘤.免疫组织化学标记显示,瘤细胞弥漫强阳性表达波形蛋白,灶性或弱阳性表达上皮膜抗原,不表达细胞角蛋白、S-100蛋白、HMB45、肌动蛋白、结蛋白、CD34、bcl-2、CD30和白细胞共同抗原(LCA)等标记.随访6例,3例复发,1例发生肺部转移.结论硬化性上皮样纤维肉瘤是纤维肉瘤的一种少见亚型,尽管瘤细胞异型性不明显,核分裂象也少见,但肿瘤可发生局部复发及远处转移,临床上应视为一种低至中度恶性的软组织肉瘤处理,组织学上则应注意与一些具有上皮样形态和硬化性间质的肿瘤相鉴别.

Sclerosing epithelioid fibrosarcoma: a clinicopathologic study of eight cases

OBJECTIVE: To study the clinicopathologic features, immunophenotype and differential diagnosis of sclerosing epithelioid fibrosarcoma (SEF). METHODS: Eight cases of SEF were investigated by light microscopy and immunohistochemistry. RESULTS: There were five males and three females. Clinically, most patients presented as a slowly growing mass. Six tumors were located in the extremities or limb girdles, and two in the trunk. Grossly, most lesions were relatively well-circumscribed with a nodular or lobulated appearance. They ranged from 2.0 to 10.5 cm in size (mean 6 cm). On sectioning, they had a gray-whitish cut surface and were firm in consistency. Microscopically, the tumors were composed of uniformly round or polygonal epithelioid cells with clear to eosinophilic cytoplasm. The tumor cells were arranged predominantly in single strands or cords and embedded in a heavily hyalinized matrix. In some areas, nests, sheets, acini or alveolar structures were also noted. Nuclei atypia and brisk mitotic activity was not evident. The mitotic count measured less than 1 per 10 high power fields. However in two cases, focal areas exhibited increased cellularity, nuclei atypia and higher mitotic activity, resembling conventional fibrosarcoma. Immunohistochemically, the tumor cells showed diffuse and strong positivity for vimentin and focal or weak positivity for EMA. There was no expression for AE1/AE3, S-100 protein, HMB45, alpha-SMA, MSA, desmin, CD34, bcl-2, CD30 and LCA. Follow-up information in six patients revealed local recurrence in 3 cases and lung metastasis in 1 case. CONCLUSIONS: SEF is a rare variant of fibrosarcoma. Despite the relatively bland appearance and low mitotic activity, the tumor is capable of local recurrence and distant metastasis. Thus, it should be considered and treated as a low to intermediate grade sarcoma. SEF needs to be differentiated from a variety of benign or malignant tumors exhibiting epithelioid features and sclerotic stromal response.