上皮样肉瘤22例临床病理分析

Epithelioid sarcoma:a clinical and pathological analysis

目的 研究上皮样肉瘤（ES）的临床病理特点.方法 分析22例ES患者的临床资料、肿瘤病理形态及免疫表型特点并进行随访,同时设立对照组,对需要与ES鉴别的多种肿瘤进行整合酶作用因子（INI1）免疫组化检测.结果 22例患者年龄范围16 -75岁,平均40.2岁;经典型及近端型ES的平均年龄分别为36.9岁和41.1岁.男女之比为1.2∶1.经典型发病部位主要位于肢体远端,而近端型常位于躯干及外生殖器区.镜下经典型常见肉芽肿样结构伴中心坏死,也可呈血管瘤样和纤维瘤样形态;近端型呈多结节性或弥漫性结构;细胞以上皮样细胞为主,异型性明显.免疫组化显示全部病例vimentin均弥漫（＋）,CKpan、CK8、EMA、CD34和CK7的阳性率分别为86.3％（19/22）、81.8％（17/22）、90.9％ （20/22）、59.1％（13/22）和4.5％ （1/22）;S-100阳性率为22.7％（5/22）,但均为弱（＋）.所有病例CD31和HMB45均为（-）.INI1在经典型和近端型ES中的失表达率分别为83.3％（10/12）和70％（7/10）;在对照组中低分化鳞状细胞癌、恶性黑色素瘤、软组织透明细胞肉瘤、上皮样血管内皮瘤、血管肉瘤INI1均为（＋）,肾恶性横纹肌样瘤均为（-）,仅1例经典型恶性外周神经鞘瘤（-）.结论 ES组织学形态多样,结合病史及联合应用INI1、CKpan、CK8、EMA、CD34等可以对大多数ES做出正确诊断.

Objective To study the clinicopathologic features of epithelioid sarcoma （ES）,with review of the literature.Methods 22 cases of ES were selected for immunohistochemical staining.Clinical and pathologic features of these cases were also reviewed.The expression of INI1,CKpan,EMA,Vim,CD34,CK8,and CK7 was detected by immunostaining.Results The patients＇ s ages ranged from 16 to 75 years （mean,40.2 years）.The median age of proximal-type ES was 41.1 years,and that of conventional ES was 36.9 years.The male-to-female ratio was 1.2∶ 1.Conventional ES mostly occurred in the distal extremities,proximal-type often in perineal,genital region and trunk.Histologically,granuloma-like architecture with central necrosis often was observed in conventional ES.In proximal-type ES,tumor cells had prominent epithelioid and/or rhabdoid features which had marked cytologic atypia.The immunohistochemical study showed Vim was positive in all cases.CKpan,CK8,EMA,CK7 and CD34 were expressed in 86.3％ （19/22）,81.8％ （17/22）,90.9％ （20/22）,59.1％ （13/22） and 4.5％ （1/22）,respectively.The immunostain for S100 which was focal and weak was found in 22.7％ （5/22）.CD31 and HMB45 were negative in all cases.The loss of INI1 was found in 83.3％ （10/12） and 70.0％ （7/10）in the conventional ES and the proximal-type ES,respectively.INI1 was detected in poorly differentiated squamous cell carcinoma,malignant melanoma,clear cell sarcoma of soft tissue,angiosarcoma and epithelioid hemangioendothelioma.INI1 was negative in all cases of malignant rhabdoid tumor and in 1 case （1/15） of malignant peripheral nerve sheath tumor.Conclusions Owing to the histologic variety,immunostaining for INI1 combined with other commonly used markers （CKpan,CK8,EMA and CD34） will be helpful for correct diagnosis of ES.