肝内肉瘤样胆管细胞癌的病理与影像表现

Pathology and Imaging Features of Intrahepatic Sarcomatoid Cholangiocarcinoma

目的探讨肝内肉瘤样胆管细胞癌(ISCC)的病理与影像学表现,以进一步提高对该病的认识。方法回顾性分析经手术病理证实的13例ISCC患者的病理、CT、MRI资料,13例患者均行CT检查,其中5例行MRI检查,分析其影像学表现。手术标本通过HE染色进行组织病理检查且进行免疫组织化学检查。结果ISCC肿块平均最大径为(61.6±22.2)mm,11例边界模糊,2例边界清晰。CT平扫肿块呈低密度,内见程度不一更低密度坏死灶。CT增强扫描表现为以坏死为主的环形或花环状强化和以实性成分为主的团块状不均匀强化,门静脉期和实质期持续强化。MRI病灶表现为T1WI低信号,T2WI高信号,信号不均匀,强化方式类似CT增强扫描,2例可见假包膜,实质期延迟强化。6例见肝内转移子灶,3例伴门静脉瘤栓形成,4例伴有腹腔淋巴结肿大。免疫组织化学CKPan、Vimentin、CK7、CK19阳性表达,Hep par1阴性表达;部分CD34、EMA阳性表达。肿瘤组织Ki-67阳性指数20%~90%。结论ISCC影像表现类似肝内肿块型胆管细胞癌,但其肿块更大,且更易合并肝内及远处转移,CT、MRI对于ISCC术前定位、定性具有一定价值。

Objective To investigate the pathological and imaging characteristics of intrahepatic sarcomatoid cholangiocarcinoma(ISCC).Methods CT,MRI and pathological findings of 13 patients with ISCC confirmed by surgery or tissue biopsy were retrospectively analyzed.13 patients underwent pre-contrast abdominal CT scan and 3-phase enhanced scan.5 patients underwent MRI examination.Specimens were stained by HE for pathological examination and followed immunohistochemistry examinations.Results The mean maximum diameter of ISCC mass was(61.6+22.2)mm,with blurred margins in 11 cases and clear margins in 2 cases.On plain CT scan,the mass showed low density with varying degrees of necrosis.CT enhancement showed ring or flower ring enhancement and mass heterogeneous enhancement,and continuous enhancement in portal and parenchymal phases.The lesions on MRI showed hypointensity on T1WI,hyperintensity on T2WI and uneven intensityThe enhancement mode was similar to CT enhancement.Two cases showed pseudocapsule and delayed enhancement in parenchymal phase.Intrahepatic metastases were found in 6 cases,portal vein thrombosis in 3 cases,and abdominal lymph node enlargement in 4 cases.Immunohistochemical staining showed CKPan,Vimentin,CK7 and CK19 positive,Hep PAR1 negative,and some CD34 and EMA positive.Ki-67 positive index was 20%-90%.Conclusion The imaging of ISCC is similar to intrahepatic mass-forming cholangiocarcinoma,but its mass is larger and associated with intrahepatic and distant metastasis frequently.CT and MRI have certain value in the diagnosis of ISCC.