儿童肝脏未分化胚胎性肉瘤的影像表现及病理分析

Imaging and pathological analysis of undifferentiated embryonal sarcoma of the liver in children

目的:分析儿童肝脏未分化胚胎性肉瘤(undifferentiated embryonal sarcoma of the liver,UESL)的超声、CT及MRI影像学表现,以提高对该病的认识水平。方法:回顾性收集2009年12月至2021年12月首都儿科研究所附属儿童医院经手术及病理证实的11例儿童UESL,分析所有患儿的超声、CT及MRI影像表现,总结其影像学特点。结果:病灶均为单发,肿块最大径11.5~19.8 cm。CT平扫显示所有病灶边缘较清楚、其内呈不均匀低密度,内可见厚薄不均的分隔;囊性密度区边缘或分隔周围可见少许片絮样软组织密度影。6例超声图像均提示实性占位,表现为混合回声的实性包块内可见大小不等的无回声区。3例MRI表现为边界清楚肿块影,T1WI呈不均匀混杂低信号,病灶内可见高信号区;T2WI呈混合高信号区和条状低信号区。9例病灶增强扫描动脉期均以边缘强化为主,8例可见迂曲增粗血管影;延迟期病灶呈持续不均匀强化,边缘持续强化,且从外围向中心充盈,强化范围增大,8例延迟期可见假包膜。结论:儿童UESL影像学表现有一定特征性,了解其影像特点并结合临床特征,有助于早期诊断。

Objective:To enhance comprehension of undifferentiated embryonal sarcoma of the liver(UESL)in children by analyzing ultrasound,CT,and MRI imaging features.Methods:A retrospective analysis was conducted on 11 cases of UESL in children,confirmed through surgery and pathology,at the Children's Hospital,Affiliated Capital Institute of Pediatrics from December 2009 to December 2021.We analyzed the ultrasound,CT,and MRI imaging features of all patients and summarized their characteristics.Results:All 11 cases presented with solitary hepatic masses ranging from 11.5 to 19.8 cm in diameter.Imaging manifestations of UESL correlated with component proportion and distribution within the masses.Lesions displayed clear boundaries in all cases.CT scans revealed mixed low density in 11 cases,with irregular floc soft tissue density shadows observed at the edge of cystic density areas or around partitions in a few cases.Ultrasound images of all six cases showed solid space-occupying masses,with varying sizes of anechoic regions within the solid mass.MRI T1WI showed mixed low intensity signal in three cases and strip/large high intensity signal areas in the lesion.T2WI revealed mixed high intensity signal and strip low intensity signal areas in 3 lesions.In the arterial phase,lesions displayed slightly to moderately heterogeneous strip/patch enhancement,primarily marginal enhancement in nine cases and thickened,tortuous arterial shadows in eight cases.In the delayed phase,lesions showed continuous uneven enhancement,with enhancement at the edge and peripheral-to-central filling observed in eight cases.Additionally,the enhancement range continuously increased in eight cases,with the false capsule sign identified in eight cases in the delayed stage.Conclusions:Imaging features of UESL in children exhibit distinct characteristics.Understanding these features,in conjunction with clinical findings,may aid in early diagnosis.