泌尿生殖系统血管周上皮样细胞瘤(PEComa)的临床特征分析

Clinical features study of perivascular epithelioid cell tumor(PEComa)in genitourinary system

目的:探讨泌尿生殖系统血管周上皮样细胞瘤(perivascular epithelioid cell tumor,PEComa)的影像学表现及病理和免疫组织化学(免疫组化)特征,以提高临床对该病的认识。方法:回顾性分析经手术病理证实的5例泌尿生殖系统PEComa患者的临床、病理及影像学资料。结果:年龄为9~63岁,平均年龄为40.8岁;男性3例,女性2例,男:女为3:2。5例患者中,4例病变位于肾脏,1例病变位于阴道;病灶直径为0.9~19.0 cm。2例均行CT平扫及增强、MRI平扫及增强检查,3例仅行CT平扫及增强检查。影像学检查结果中,2例患者的CT平扫图像可见较小病灶,大小分别为0.9 cm×0.9 cm×1.0 cm、2.1 cm×1.7 cm×2.0 cm,密度均匀,增强扫描呈均匀明显强化;MRI平扫信号均匀,增强扫描呈均匀强化。另3例患者的病灶较大,最大径约19 cm,CT平扫提示病灶密度不均匀;CT增强扫描较大病灶则呈不均匀明显强化,可见液化坏死区,病灶内或周围出现粗大血管影。术后大体标本显示肿瘤切面呈灰白、灰红色,可见有出血,质韧,有包膜。镜下可以见肿瘤形态为上皮样、梭形,胞浆丰富,嗜酸性、颗粒状,空泡状,其核仁明显,核分裂象少,其内可见大片坏死。免疫组化检查示,PEComa组织中黑色素瘤抗体[Melanoma marker(human)monoclonal antibody,HMB45]呈阳性表达,Melan-A、肌源性抗体(Myogenic antibody,SMA)、CD34和S-100呈部分阳性表达。结论:泌尿生殖系统PEComa的影像学表现有一定特点,病灶较小(最大径<2 cm)时在CT图像密度均匀,CT增强呈均匀明显强化,强化程度低于正常肾实质;在MRI图像上信号均匀,MRI增强呈均匀明显强化。病灶较大时,在CT图像上密度不均,可出现液化坏死区,CT增强扫描呈不均匀强化,实性部分强化明显,可见粗大血管供血,内部坏死区未见明显强化。

Objective:To investigate the imaging features and clinicopathological features of perivascular epithelioid cell tumor(PEComa)of the genitourinary system,and to improve the understanding of PEComa.Methods:The clinical,pathological and imaging data of 5 patients with PEComa confirmed by surgical pathology were retrospectively analyzed.Results:The age of the five patients ranged from 9 to 63 years,with a mean age of 40.8 years Among the 5 patients,4 lesions were located in the kidney and 1 lesion in the vagina.The diameter of the lesion is 0.9~19 cm.Postoperative gross specimens showed that section of the tumor was gray and gry-red,with bleeding,toughness and envelope.Microscopically,the tumor was epithelioid and fusiform,with abundant cytoplasm,eosinophilic,granular,vacular,obvious nucleolus,few mitotic images,and large necrosis.CT plain scan and enhanced examination and MRI plain scan and enhanced examination were performed in 2 cases,only CT plain scan and enhanced examination in 3 cases.Homogeneous enhancement was observed in 2 cases,and uneven and obvious enhancement was observed in 3 cases of larger lesions,with liquefaction necrotic area.There are large vascular shadows in or around the lesion.Immunohistochemistry showed positive expression of HMB45,and partial positive expression of MELAN-A,SMA CD-31,CD34 and S-100.Conclusions:The imaging findings of perivascular epithelioid cell tumor of genitourinary system have certain characteristics,The CT image density is uniform and the enhancement is uniform and obvious,and the enhancement degree is lower than with of normal renal parenchyma.MRI image signal is uniform,the enhancement is uniform and obvious.When the lesion is large,the CT image density is uneven,liquefaction necrotic area may appear,the enhancement scan shows uneven enhancement,the solid part of the enhancement is obvious,and the blood supply of large vessels is visible,and the internal necrotic area does not show obvious enhancement.