低度恶性肌纤维母细胞性肉瘤

Low-grade myofibroblastic sarcoma

目的探讨低度恶性肌纤维母细胞性肉瘤的临床病理学特征、免疫学表型及鉴别诊断。方法对1例发生于后腹膜的低度恶性肌纤维母细胞性肉瘤进行光镜观察、免疫组化标记并结合文献进行复习。结果肿瘤细胞呈梭形,排列成束,显示中度异型性,可见核分裂像(3～4个/10HPF)。免疫表型:瘤细胞弥漫性广泛表达Vim、SMA,不表达MSA、Des、和S100蛋白。结论低度恶性肌纤维母细胞性肉瘤是一种少见的软组织肉瘤,组织学形态及免疫表型显示瘤细胞具肌纤维母细胞性分化。应与纤维瘤病、纤维肉瘤和平滑肌肉瘤相鉴别。

Objective To study the clinicopathologic, immunohistochemical features and diffential diagnosis of low-grade myofibroblastic sarcoma. Methods One case of low-grade myofibroblastic sarcoma of the left maxillary sinus was evaluated by light microscopy, immunohistochemistry,and related literature was reviewed. Results The tumor cells were spindle and arranged in fasciculus, The nuclei displayed mild to moderate atypia with mitotic figures counted 3-4/10HPF. Immunohistochemically , they were diffusely strong positive for Vim and SMA, but negative for MSA, Des, and S100 protein. Conclusion Myofibroblastic sarcoma is a rare entity of soft tissue tumors, most of which are of low-grade malignancy. The light microscopic and immunohistochemical features all favor a myofibroblastic differentiation. Low-grade myofibroblastic sarcoma should be distinguished from fibromatosic, fribros sarcoma and leiomy sarcoma.