1例硬化性滑膜肉瘤的临床病理观察

Clinicopathological features of sclerotic synovial sarcoma

目的探讨硬化性滑膜肉瘤的病理特征、诊断及鉴别诊断。方法分析1例发生于小腿软组织的硬化性滑膜肉瘤的临床表现、病理形态和免疫组织化学染色、特殊染色特征及其细胞遗传学的特异性改变,并复习相关文献。结果首次报告硬化性滑膜肉瘤1例。患者29岁,病史13年,肿瘤内见大量不规则的梁索状胶原成分,瘤细胞稀疏,围绕在胶原周围,瘤细胞梭形,部分为上皮样,围绕小血管生长,肿瘤内部分区域见钙化及骨化。免疫组化染色结果显示EMA(+),CK(局部+),Vimentin(++),Bcl-2(+),CD99(++),P53(+50%-75%),CD31、CD34、Desmin、SMA均为阴性;硬化的间质区域网织纤维及AB染色阳性,PAS染色阴性;FISH检测提示:SS18(18q11.2)染色体易位。结论硬化性滑膜肉瘤是一种非常罕见的特殊类型的滑膜肉瘤,可结合免疫组织化学染色及分子检测与骨旁骨肉瘤、骨化性肌炎、纤维肉瘤、骨促结缔组织增生性纤维瘤、血管外皮细胞瘤等肿瘤进行鉴别。

Objective To study the pathological features of sclerotic synovial sarcoma（SS） and its diagnosis and differential diagnosis. Methods Clinical manifestations, pathological morphology, immunohistochemical staining, special staining and specific changes in cytogenetics of leg sclerotic SS in a patient were analyzed with the related literature reviewed. Results This case of leg sclerotic SS was first reported. The patient was 29-year-old with a 13-year history of left leg sclerotic SS. A large number of irregular trabecular collagens were found in the tumor with a rarefaction of tumor cells and spindle cells around the collagens, some of which were epithelial cells growing around the small blood vessels, and calcification and ossification in certain areas of the tumor. Immunohistochemical staining showed that the tumor was positive for EMA（epithelial memberane antigen）, CK（cytokeratin）, vimentin, Bcl-2, CD99 and negative for CD31, CD34, desmin and SMA. P53 positive cells accounted for 50%-75%. Reticulum fibers in sclerotic interstitial area were positively stained with AB while PAS staining was negative. FISH showed SS18（18q11.2） chromosome translocation. Conclusion Sclerotic SS is an extremely rare type of synovial sarcoma. Its differential diagnosis can be made with immunohistochemical staining and molecular detection from parosteal osteosarcoma, myositis ossificans, fibrosarcoma, desmoplastic fibroma of bone and hemangiopericytoma.