肾恶性血管周上皮样细胞肿瘤的临床病理特征

目的:探讨肾恶性血管周上皮样细胞肿瘤（PEComa）的临床病理特征、免疫表型及分子遗传学特点、诊断与鉴别诊断以及治疗方式。方法:通过深入学习2例肾恶性血管周上皮样细胞肿瘤的组织形态特点并复习相关文献，归纳该肿瘤的诊断和鉴别诊断要点、探讨其免疫表型和分子遗传学特征，总结现有的治疗策略。结果:2例分别发生在48岁女性及62岁男性患者，肿瘤直径均大于5 cm，均以上皮样细胞为主，体积大，胞浆丰富，嗜酸性，单核或多核，细胞异型性明显，可见大片坏死，核分裂象约(2~3)个/50 HPF。在例1中，可见丰富纤薄的间质血管将肿瘤分隔成巢状，腺泡样结构;在例2中，肿瘤囊性变，呈多囊性结构，囊壁由肿瘤细胞构成，上皮样细胞间可见梭形细胞区域。2例肿瘤HMB45均局灶阳性，MelanA弥漫强阳性，TFE3蛋白表达均阴性。在例1中，肿瘤细胞不表达肌源性标记（SMA、Desmin均阴性）;而在例2中，肿瘤的梭形细胞区域SMA和Desmin局灶阳性。结论:肾恶性血管周上皮样细胞肿瘤属罕见疾病，需对该肿瘤加强学习认识，避免漏诊和误诊，治疗主要以手术切除为主，术后多予随访，但预后较差，分子靶向的个性化治疗将成为趋势。

Clinicopathologic features of malignant parivascular epithelieid cell tumor of the kidney

Objective:To investigate the clinicopathological features,immunophenotype,molecular genetic characteristics,diagnosis and differential diagnosis and treatment of malignant perivascular epithelioid cell tumor（PEComa) of the kidney.Methods:Based on in-depth study of the morphological characteristics in 2 cases of renal malignant perivascular epithelioid cell tumor and review of the related literatures,diagnosis and differential diagnosis were concluded,immunophenotype and molecular genetic features were explored,existing treatment strategies were summarized.Results:2 cases respectively occurred in a 48-year old female and a 62-year old male patient with tumors greater than 5 cm in diameter,the tumor cells were composed of large atypia epithelioid cells with abundant eosinophilic cytoplasm,mononuclear or multinuclear,obvious heteromorphic characteristics,massive necrosis and mitotic figures about (2~3)/50 HPF.In case 1,tumor cells were divided into nests or acinar with visible rich slim stromal vascular.In case 2,the tumor presented cystic and polycystic structure with thick cyst wall composed of tumor cells,in which the spindle cell area is visible between the epithelioid cells.HMB45 was focal positive,MelanA was strongly positive and TFE3 protein expression was negative in both cases.The tumor cells in case 1 did not express myogenic markers（both SMA and Desmin were negative),whereas spindle cell regions in case 2 were local positive for SMA and Desmin.Conclusion:PEComa,a rare malignant renal disease,must be explored extensively and delicately to avoid missed diagnosis or misdiagnosis.Surgical resection with more follows-up is a main strategy for treatment though the prognosis is poor,thus,the individualized treatment of molecular targeting will become a trend.