近端型上皮样肉瘤1例及文献复习

Proximal-type epitheliod sarcoma:report of one case and review of the literature

目的探讨近端型上皮样肉瘤(proximal-type epitheliod sarcoma,PES)的临床病理特点及鉴别诊断。方法报道1例PES患者的临床资料,并对其进行组织学观察、免疫组化(EnVision-plus法)标记及电镜观察。结果患者女性,24岁。临床主要表现右侧大阴唇逐渐增大的无痛性肿块。组织学特征:瘤组织呈结节状生长,瘤细胞椭圆形、多边形,胞质嗜双色或嗜酸性,核空泡状,有明显核仁。常见横纹肌样细胞,未见肉芽肿样改变。免疫表型:瘤细胞vimentin、β-catenin阳性,EMA局灶阳性;而SMA、MyoD1、desmin、CD117、S-100、HMB-45、Melan A、CD99、Syn、CD57、CKAE1/AE3、CK8/18、CK19、CA125、CEA、FⅧRAg、CD31、CD34、Calretinin、CD45和CD68阴性。电镜:细胞胞质内见较多线粒体、少量粗面内质网及溶酶体,未见黑色素小体、神经内分泌颗粒及肌丝,细胞间连接不明显,未见肿瘤间质。结论PES为一种罕见的软组织肿瘤,与经典型ES相比,具有独特的组织学特征,并具有更强的侵袭性。

Purpose To explore the clinicopathologic characteristics and differential diagnosis of proximal-type epitheliod sarcoma（PES）.Methods To reported the clinical data of a case of PES and reviewed the histopathologic,immunohistochemical（using EnVision-plus kit） and ultrastructural features.Results The patient was a 24-year-old female.She presented with a gradually increasing,painless mass in her right labium majus.Histopathologically,the tumor displayed multinodular pattern of growth.The tumor cells were oval or polygonal with vesicular nuclei,prominent nucleoli and eosinophilic or amphophilic cytoplasm.Rhabdoid features were frequently observed,and granuloma-like alterations seldom observed.Immunophenotype：the tumor cells were diffusely positive for vimentin,β-catenin,and focally positive for EMA,while negative for SMA、MyoD1、desmin、CD117、S-100、HMB-45、Melan A、CD99、Syn、 CD57、 CKAE1/AE3、CK8/18、CK19、CA125、CEA、FⅧRAg、CD31、CD34、Calretinin、CD45 and CD68.Electron microscopy findings：the cytoplasm of the tumor cell cantained many mitochondria,a small amount of rough endoplasmic reticulum and lysosomes.Melanosomes,neuroendocrine particles and myofilaments weren＇t observed,the junctional structures between the cells weren＇t obvious,tumor mesenchymal couldn＇t be found.Conclusions PES is a rare soft tissue tumor.Compared to the classic type ES,it has the unique histological characteristics,and is more aggressive.