髓外浆细胞瘤的CT及MRI表现

CT and MRI features of extramedullary plasmacytoma

目的:分析不同部位髓外浆细胞瘤(extramedullary plasmacytoma,EMP)的CT及MRI表现,以提高对该病影像诊断及鉴别诊断的水平。方法:观察7例经病理证实EMP的CT及MRI表现,对病灶部位、密度、信号、强化特点、邻近骨质及软组织受侵情况等方面进行综合性分析。结果:7例病例中,病灶位于鼻咽部、小肠各2例,咽后间隙、肺内及肾脏各1例,均为单发病灶。鼻咽部、咽后间隙及小肠病灶表现为边界清晰的软组织肿块,CT平扫呈等或等低密度;MRI平扫T1WI呈等或稍低信号,T2WI呈等或稍高信号,T2WI-FS呈高信号,DWI呈高信号。肺内及肾脏病灶CT平扫表现为边界模糊的等或稍高密度肿块,其内密度不均匀,肾脏病灶侵犯肾盂及输尿管。其中1例鼻咽部病灶和肾脏病灶患者行CT增强扫描,表现呈中度至明显强化,病灶内或周边见迂曲增粗的血管影。结论:EMP具有一定的影像学特征,但其表现仍缺乏特异性,还需结合病理及免疫组化予以确诊。CT和MRI联合检查能明确EMP的病变范围及周围组织受累情况,对该病临床治疗方案的选择及疗效评估具有重要意义。

Objective To analyze the CT and MRI features of extramedullary plasmacytoma(EMP)in different parts for improving the imaging diagnosis and differential diagnosis of the disease.Methods The CT and MRI features of 7 patients with pathologically confirmed EMP were reviewed retrospectively on the lesion site,density,signal,enhan-cement characteristics,adjacent bone and soft tissue invasion.Results All the 7 patients had solitary lesions,of which,there were two ones in the nasopharynx and another two ones in the small intestine,and the remained three ones located in the retropharyngeal space,the lung and in the kidney respectively.The lesions in the nasopharyngeal,retropharyngeal space and small intestine appeared as well-defined soft tissue masses with equal or equal low density on CT scan;MRI scan revealed equal or slightly low signals on T1WI,equal or slightly high signals on T2WI,high signals on T2WI-FS and high signals on DWI.CT scan of the lung and kidney lesions showed faintly defined iso-or slightly dense masses with heterogeneous density,and the kidney lesion invaded the renal pelvis and ureter.The patient with a kidney lesion and one with a nasopharyngeal lesion underwent CT-enhanced scanning and showed moderate to marked enhancement with tortuous and thickened vascular shadows in or around the lesions.Conclusion EMP has certain imaging features,which are lack of specificity and have to be combined with pathology and immunohistochemistry examinations for definite diagnosis of EMP.Combined CT and MRI examination can clarify the extent of the EMP lesion and the surrounding tissue involvement,which is of significance for selecting and evaluating clinical treatment options for EMP.