下肢软组织黏液性-圆细胞型脂肪肉瘤的MR表现

目的探讨下肢软组织黏液性-圆细胞型脂肪肉瘤的MR表现及其与病理组织学的联系。方法回顾性分析6例手术病理证实为下肢软组织黏液性或黏液性-圆细胞型脂肪肉瘤患者的MR表现,观察肿瘤的位置、大小、形态、边界、内部结构及在T1W I、T2W I、T2脂肪抑制像(SPIR)和静脉注射Gd-DTPA后信号特点。结果肿块均位于下肢深部肌肉间隙内,形态多不规整,边界清楚,平均最大径约为15.2 cm,内部可见排列紊乱的纤维间隔,大部分纤维间隔厚度超过2 mm。T1W I肿块与周围骨骼肌相比呈均匀或不均匀等信号或略高、略低信号,T2W I呈高信号,脂肪抑制像肿块信号强度无减低,增强扫描见不同程度不均匀强化。结论MR可对下肢黏液性-圆细胞型脂肪肉瘤的诊断提供有价值的信息。

MR Findings of Myxoid-round Cell Liposarcoma of the Lower Extremities

Objective To observe the MR findings of myxoid-round cell liposarcoma of the lower extremities and to evaluate therelationship between MR findings and pathologic features. Methods MR findings of 6 myxoid-round cell liposarcomas of the lowerextremities confirmed pathologically were retrospectively reviewed,including tumor's location,size,morphology,internal architecture and signal intensity characteristics on T_1WI,T_2WI and SPIR T_2WI and the pattern of enhancement.Results All tumors were located in thedeep space among skeletal muscles of the lower extremities,with unregular shape,sharp borber and thick septal structures.Tumors werehomogeneous or heterogeneous isointense on T_1WI and hyperintense on T_2WI relative to the signal intensity of skeletal muscles and heterogeneous enhancement after the injection of GdDTPA.Conclusion MRI may lead to a correct diagnosis of myxoidround cell liposarcoma of the lower extremities.