骨外黏液性软骨肉瘤28例临床病理分析

Extraskeletal myxiod chondrosarcoma:a clinicopathological analysis of 28 cases

分析骨外黏液性软骨肉瘤（EMC）的临床特征、病理学形态及免疫学表型,探讨其鉴别诊断。方法对28例骨外黏液性软骨肉瘤的临床病理学资料、免疫表型和基因测序进行回顾性复习。结果 28例中男性16例,女性12例;年龄16-72岁。11例发生于大腿,4例发生在臀部,前臂、腹股沟区、肩部各2例,会阴部、小腿、骶尾部、胸部、背部、腹壁和腮腺部各1例。肿瘤最大径1-19 cm,切面呈灰白色,黏冻样,境界不清。镜下肿瘤细胞由纤维组织分割排列成结节状,瘤细胞体积中等大小,胞质丰富,间质富含黏液,部分病例可见出血、坏死。免疫组化：瘤细胞vimentin（＋）,8例S-100、9例Syn、3例EMA和2例NSE（＋）。Ki-67阳性指数大部分〈10%,只有2例富细胞型为30%。结论骨外黏液性软骨肉瘤是一种低-中度恶性的软组织肿瘤,其分化来源未定,常好发于中老年人,以肢体近端为好发部位,特别是大腿和臀部。

Objective To study the clinical features,pathological mophology and immunophenotyping of extraskeletal myxiod chondrosarcoma（ EMC）,with emphasis on the diagnosis and differential diagnosis of EMC. Methods The clinicopathological data,immunophenotype and gene sequencing were retrospectively reiewed. Results In the 28 patients,there were 16 males and 12 females,aged 16 - 72 years. Eleven cases occurred in thigh,four in buttocks,two in forearm,inguien and shoulder,one in leg,back,perineum,sacrum,chest,abdomen,and salivary gland,respectively.The tumor size varied from 1 - 19 cm in diameter. It was myxoid,gray and white on cut surface. Microscopically,the tumor cells were small round,with pink cytoplasm,arranged in lace like pattern,embedded in rich myxoid background.Hemorrhage and necrosis were noted in some cases. It was positive for vimentin for all of them,some were positive for S-100（8 cases）,SYN（9 cases）,EMA（3 cases）,and NSE（2 cases） in immunohistochemistry. Ki-67 index was more than 10% in most of cases,that in two cellular cases being more than 30%. Conclusions EMC is a low to intermediate grade malignant tumor,commonly found in old person. It mainly occurs in limbs,especially in the thigh and buttocks.