滑膜肉瘤的MRI诊断分析

Diagnosis Analysis of MRI Examination of Synovial Sarcoma

目的分析滑膜肉瘤(synovial sarcoma,SS)的MRI征象,提高认识,减少误诊。方法对我院收治并经病理检查确诊的SS 6例的MRI影像资料及病理检查结果进行回顾分析。结果本组病变位于膝关节2例,肘关节、腹股沟、小腿及腰椎各1例。MRI影像表现:1例肿块位于腰椎前方,边界不清,相应椎体骨质破坏并累及腰大肌,后腹膜淋巴结增大。5例肿块呈类圆形或椭圆形,边界清晰,其中3例软组织肿块表现为T1WI稍高信号,T2WI混杂高信号,有散在斑点状、线条状分隔样低信号及囊状等、高、低信号,增强后肿块实质性部分明显不均匀强化,条状分隔明显强化;另2例肿块分别位于肘关节及腹股沟肌肉间隙内,体积相对较小,T1WI稍高信号,T2WI较高信号,信号均匀,瘤壁较厚。结论 SS MRI表现有一定特征性,关节周围有边界清楚的软组织肿块,T2WI以低信号分隔成多房高、等、低混杂信号,增强后肿瘤实质成分明显强化,高度提示SS,但其最终诊断仍有赖于病理形态学、免疫组织化学或SYT-SSX融合基因检查。

Objective To analyze the imaging features of synovial sarcoma （SS） so as to improve awareness. Methods MRI imaging data and pathological examination results of 6 patients with SS confirmed by pathological examination in our hospital were retrospectively analyzed. Results There were 2 patients with lesion located in knee joint, one in elbow joint, one in fold inguen, one in cnemis and one in lumbar vertebrae. MRI imaging manifestations： one tumor located in vertebra lumbalis eroded thebody of vertebra, obscure boundary and encroached the greater psoas muscle with lymphadenectasis ; 5 patients＇tumors with round or ellipse shapes showed well-defined margins, including 3 soft tissue tumors with slightly hyperintense on T1WI, promiscuous hyperin- tense on T2WI, dispersive mottling and line disjunctive hypointensity and equal, high and low signals of cystic forms. The enhance- ment of synovial sarcomas was usually pronounced in inhomogeneous, and line separation was obviously strengthened; two tumors lo- cated in interspace of elbow joint and inguen muscles showed little volumes, slightly hyperintense on T1WI, hyperintense on T2WI, symmetrical signal and thick tumors wall. Conclusion SSMRI manifestations have a certain marks. Soft tissue masses with well-de- fined, MR images may indicate that hypointensity is divided into high, equal and low signals on T2WI, intensive parenchyma com- ponent of tumors by enhancement and should be considered as SS, but final diagnosis should depended on pathomorphology, immu- nohistochemistry and SYT-SSX fused gene examinations.