原发性肺动脉肉瘤的CT及临床病理特征

CT and clinicopathological features of primary pulmonary artery sarcoma

目的:探讨原发性肺动脉肉瘤(PPAS)的CT及病理特征表现。方法:对13例PPAS的CT图像及病理资料进行回顾性分析,在CT上主要观察肿瘤部位、范围、形状、密度、周围组织侵袭及转移等情况,同时分析肿瘤病理表现,总结其特征表现。结果:肿瘤主体位于主肺动脉-肺动脉干12例,位于肺动脉干1例;肿瘤累及肺动脉肺叶分支9例。13例PPAS病变段肺动脉明显局限性增粗,相应区域主肺动脉及近端肺动脉完全性或部分充盈缺损,呈铸型、息肉样或结节状改变,病变段肺动脉内壁边界模糊不清。其中5例病变向动脉壁外侵犯,穿透血管壁,于纵膈内形成肿块;1例侵入左肺静脉主干内,形成息肉样肿块影;1例继发左肺上叶结节状孤立性转移瘤。平扫肿瘤呈不均匀等密度或稍低密度,增强后动脉期见不均匀强化,静脉期持续强化,延迟期强化减低。肺内多发小片状、片状渗出实变灶4例,其中渗出实变灶伴空洞1例;心包少量积液2例,胸腔少量积液2例。镜下肿瘤细胞主要由不规则血管腔隙、梭形细胞构成,部分区域有黏液样变,部分区域见坏死,细胞核大异型。免疫表型:瘤细胞Vimentin弥漫阳性,CD34和CD31呈阳性。结论:PPAS多侵犯主肺动脉和左右肺动脉干,易累及2个以上部位;病灶多呈铸型、息肉样或结节状,平扫呈密度不均匀,增强呈不均匀强化;肿瘤有较强的侵袭性;瘤细胞Vimentin弥漫阳性,CD34和CD31呈阳性。这些表现能够对PPAS认识和诊断提供一些帮助。

Objective:To analyze the CT and pathological features of primary pulmonary artery sarcoma(PPAS).Methods:Retrospective analysis was conducted on CT images and pathological data from 13 cases of PPAS.CT scans focused on observing the location,extent,shape,density,invasion and metastasis of surrounding tissues.Pathological manifestations of the tumor were also analyzed to identify potential characteristics.Results:In 12 cases,the main body of the tumor was located in the main pulmonary artery pulmonary artery trunk,while in 1 case it was found in the pulmonary artery trunk.Tumor involvement was observed in the pulmonary lobar branches of the pulmonary artery in 9 cases.In 13 cases,PPAS indicated significant localized thickening of the pulmonary arteries,with complete or partial filling defects in corresponding areas of the main pulmonary artery and proximal pulmonary artery.These defects presented as cast,polypoid,or nodular changes.The inner wall boundary of the diseased segment of the pulmonary artery appeared unclear.There were 5 cases that showed lesion invasion outside the arterial wall,penetrating the vascular wall and forming a mass within the mediastinal.One case revealed invasion of the main left pulmonary vein,forming a polypoid mass shadow.Furthermore,one case exhibited secondary solitary nodular metastasis in the left upper lobe of the lung.On plain scanning,the tumor appeared uneven or slightly lower in density,with uneven enhancement observed in the arterial phase,continuous enhancement in the venous phase,and reduced enhancement in the delayed phase after enhancement.Multiple small and patchy exudative solid lesions were observed in 4 cases,including 1 case with cavity.Mild pericardial effusion was detected in 2 cases,along with mild pleural effusion.Microscope examination revealed tumor cells were predominantly irregular vascular cavities and spindle cells.Some areas exhibited mucinous changes,necrosis,and large nuclei atypia.Immunophenotype:tumor cells showed diffused positivity for Vimentin,and positivity for CD34 and CD31.Conclusion:PPAS mostly invades the main pulmonary artery,as well as the left and right pulmonary artery trunks,with involvement of more than 2 sites commonly observed.The lesions are mostly cast-like,polypoid,or nodular,exhibiting uneven density on plain scans and uneven enhancement on enhanced scans.The tumor exhibits strong invasiveness.The tumor cells showed diffused positive for Vimentin,while CD34 and CD31 are positive.These findings can aid in the recognition and diagnosis of PPAS.