原发性肝脏恶性血管源性肿瘤的影像表现并文献复习

目的探讨原发性肝脏恶性血管源性肿瘤的影像表现。方法回顾性分析10例原发性肝脏恶性血管源性肿瘤的影像表现,并与肝移植或活检后的病理结果进行对照分析。结果7例肝上皮样血管内皮瘤(EHE),4例行多层螺旋CT(MDCT)检查,平扫为不均匀低密度,增强扫描动脉期1例呈环状强化,延迟期3例呈厚壁的环状强化;6例患者行MRI检查,平扫T1WI为低信号,T2WI呈不均质高信号,扩散加权成像(DWI)(b值为800 s/mm2)表现为环状及结节状高信号各3例,增强后4例在动脉早期至延迟期表现为逐渐增厚的环状强化,其中1例在病灶周围可见低信号环;2例在动脉期表现为轻度环状强化,延迟期1例呈向心性轻度强化,另1例呈结节状强化。本组中5例进行了导管栓塞治疗。2例肝血管肉瘤(HA),平扫T1WI显示肝内弥漫性低信号,其中1例可见局灶性高信号;T2WI显示弥漫性大小不等的高信号;DWI表现为弥漫的集合小结节状高信号;增强扫描后动脉早期可见病变内弥漫的多中心小结节状强化,静脉期至延迟期呈向外扩散并持续性强化。1例肝脏恶性血管外皮细胞瘤(HPC),CT平扫为边界清楚的不均匀低密度灶,增强扫描动脉期可见轻度的散在斑片状强化,延迟期呈"流出"表现。结论肝脏血管源性肿瘤的强化具有一定的特征性,即EHE为渐进性的厚壁强化,HA为持续性的离心性强化,HPC类似于肝细胞癌的强化。

Primary Malignant Hepatic Tumors of Vascular Origin:Imaging Appearances and Literature Review

Objective To investigate radiologic findings of primary malignant hepatic tumors of vascular origin.Methods The radiologic findings of 10 cases of primary malignant hepatic tumors of vascular origin were retrospectively reviewed and compared with pathologic findings obtained after liver transplantation and liver biopsy.Results Hepatic epithelioid hemangioendothelioma in 7 cases,4 patients underwent MDCT scan.Unenhanced CT scan showed inhomogeneous hypoattenuating lesion.There was ring enhancement with thick wall in 3 cases and mild ring enhancement in the delayed phase in 1 case.Six cases were performed MR examination,the lesions demonstrated hypointensity on T1WI,inhomogeneous hyperintensity on T2WI.DWI(b=800 s/mm2)showed ring hyperintensity in 3 cases and nodular hyperintensity in 3 cases.Two patterns of enhancement were observed after intravenous contrast admnistration:(1)four cases showed progressively thickened ring enhancement from early arterial phase to delayed phase,and low signal rings were seen around the lesion in 1 case.(2)Two cases presented mild ring enhancement in the arterial phase,one presented mild centripetal enhancement in delayed phase,and the other presented nodular enhancement.There were 2 cases of Hepatic angiosarcoma in which unenhanced T1WI showed diffuse hypointensity in the liver,including focal hyperintensity in 1 case.DWI showed diffuse aggregative small nodular hyperintensity.The diffuse,multicentric nodular enhancement was seen in early arterial phase,centrifugal enhancement in the venous phase and progressive enhancement in the delayed phase.1 case was Hepatic hemangiopericytoma:unenhanced CT scan showed well-circumscribed inhomogeneous hypoattenuation.Mild patchy patchy enhancement was observed in the arterial phase,and wash out was observed in the delayed phase.Conclusion Primary malignant hepatic tumors of vascular origin had characteristic imaging features.Hepatic epithelioid hemangioendothelioma showed progressive thick ring enhancement.Hepatic angiosarcoma showed centrifugal progressive enhancement.Hepatic hemangiopericytoma showed the pattern of enhancement of hepatocellular carcinoma.