低度恶性肌纤维母细胞肉瘤的影像学表现

Imaging findings of low-grade myofibroblastic sarcoma

目的分析低度恶性肌纤维母细胞肉瘤(LGMS)的影像学表现,并与病理相对照。方法回顾性分析12例(13个病灶)经手术病理证实的LGMS的乳腺钼靶X线、CT、MRI表现特征及其病理诊断。结果 12例中,男4例,女8例,中位年龄44岁;11例单发,1例多发。12个病灶呈分叶和(或)膨胀性生长,边界清楚,瘤周水肿不明显,1个病灶呈浸润性生长。病灶大体T1WI呈均匀低信号,T2WI呈不均匀较高信号,内可见多条低信号分隔,偶有囊变、出血,增强后呈明显厚壁花环样强化。CT平扫病灶大体呈中等稍低密度,可见大片状钙化,实质部分CT值为30～47HU;增强后呈渐进性均匀或环形强化;乳腺钼靶X线片表现为分叶状中等稍高密度影。12例中,2例发生远处转移,3例复发,其中1例复发8次。影像学表现与病理结果相符。结论 LGMS的影像学表现具有一定特征性。

Objective To analyze imaging appearances of low-grade myofibroblastic sarcoma （LGMS） compared with pathologic findings. Methods Twelve patients （13 lesions） of LGMS confirmed histopathologically were analyzed. MRI, CT or mammography morphological characteristics of lesions were observed and compared with pathologic findings. Results Four patients were male, 8 patients were female, with the median age of 44 years. Twelve tumors were lobulated solid and/or grew expansively, with clear and sharp boundary, without peritumoral edema （12 lesions）, while 1 tumor grew in- vasively. Single lesion was found in 11 patients and multiple in 1 patient. TlWI showed hypointense lesions, T2WI showed mild heterogeneous hyperintense lesions, and garland-like or heterogeneous enhancement revealed in the parenchymal of the tumor. CT could find calcification in the lesions, the plain CT value of the tumor paranchyma were a0--47 HU, and pro- gressive enhancement was observed after injection of contrast agent. Mild high density was found in mammography in breast lesion. Among all 12 patients, metastases were found in 2 patients, and reoccurrence happened in 3 patients, 1 pa- tient had 8 times of reoccurrence. Imaging appearances were consistent with the histopathologic results. Conlusion Ima- ging appearances of LGMS are characteristic.