CD99阳性的间叶性软骨肉瘤5例并文献复习

CD99 positive mesenchymal chondrosarcoma: a report of 5 cases and review of the literature

目的 分析间叶性软骨肉瘤的病理形态学、诊断及鉴别诊断。方法 报道 5例间叶性软骨肉瘤 ,从病理组织学、免疫组化等方面进行观察。结果 5例间叶性软骨肉瘤 3例位于上腭 ,1例位于右枕顶叶 ,另 1例位于左臀肌内。肿瘤大体呈鱼肉状 ,并混有质硬的软骨、碎骨或钙化组织。组织学由血管外皮瘤样构型的原始未分化小细胞和相对成熟透明的软骨小岛构成。免疫组化未分化小细胞呈不同程度CD99膜阳性 ,Vim弱阳性 ;S 10 0局限于软骨陷窝内软骨细胞或软骨母细胞。结论 此病在未分化小细胞区找到相对成熟的软骨组织是诊断要点 。

Objective To investigate the histopathological features of mesenchymal chondrosarcoma and its differential diagnosis. Methods Five cases of mesenchymal chondrosarcoma were studied with histopathological observation and immunohistochemical staining. Results The tumors located at superior palate (3 cases), brain (1 case) and the buttock muscle ( 1 case). Grossly, the tumors were fish-meat like appearance, mixed with hard cartilages, broken bone and calcification. Microscopically, the tumors were composed of the primitive undifferentiated cells arranged in hemoangiopericytoma-like structure, and well-differentiated hyaline cartilage islets. Immunohistochemically, the undifferentiated small cells were positive for CD99 with a membranous pattern.Conclusions The key point for the diagnosis of this tumor is to find out the islands of relatively mature cartilage within undifferentiated small cell zones and CD99 expression helps make a definite diagnosis.