肝脏血管平滑肌脂肪瘤9例临床病理分析

目的探讨肝脏血管平滑肌脂肪瘤(hepatic angiomyolipoma,HAML)的临床病理特点、诊断及鉴别诊断。方法对9例HAML进行临床病理学观察与免疫组化标记及复习有关文献。结果 9例HAML年龄28～56岁,平均44.2岁,均无结节硬化症。术前影像诊断多数为肝癌。眼观:肿瘤直径1.2～14 cm。肝左叶4例、肝尾状叶3例和肝右叶2例。肿瘤境界清楚,无包膜,质地脆、易碎,可见出血、坏死。镜检:瘤组织由上皮样细胞、平滑肌样细胞、脂肪组织和厚壁血管组成。上皮样细胞体积大或巨大,呈多边形,胞质丰富,嗜酸性或空泡状,核仁明显,可见核内包涵体,偶见多核巨细胞。平滑肌样细胞呈梭形,9例中有4例几乎缺如脂肪组织。瘤细胞弥漫性或巢团状排列。瘤组织出血、坏死明显,呈浸润性边缘。免疫组化标记:瘤细胞HMB-45及Melan-A阳性,SMA和vimentin散在阳性,CK、EMA、AFP均阴性。结论 HAML是一种罕见的间叶组织源性肿瘤,多见于女性,组织学上以单一方向分化的大上皮样细胞为主,瘤细胞较为特异的表达HMB-45及Melan-A。免疫组化标记可与其它肝脏肿瘤鉴别。     

儿童肾脏上皮样血管平滑肌脂肪瘤病理特点

目的 探讨儿童肾脏上皮样血管平滑肌脂肪瘤(epithelioid angiomyolipoma,EAML)免疫标记的表达特点及其对临床病理诊断、鉴别诊断和预后的意义.方法 对1例肾脏EAML临床资料进行复习,进行光镜观察和免疫组化染色,并随访.结果 光镜下肿瘤由典型性的上皮样细胞组成,细胞核有异型性,核分裂象可见,有坏死和出血;淋巴结内未见上皮样肿瘤细胞累及.免疫标记:瘤细胞vimentin、SMA、HMB-45、Melan-A、CD68均阳性;而CK(AE1/AE3)、EMA、S-100、CD10、CD34、CD117、ER、PR、Ki-67和p53均为阴性.患者手术后状态良好,无肿瘤局部复发和转移征象.结论 肿瘤以上皮样细胞增生特征为主,临床表现和组织学表现易与肾脏肿瘤及其他肿瘤相混,寻找经典血管平滑肌脂肪瘤的结构和肿瘤细胞表达HMB-45和SMA对诊断和鉴别诊断至关重要.而细胞的不典型性、核分裂、出血和坏死可能只表明肿瘤的恶性潜能;淋巴结受累、肾静脉瘤栓均不是恶性的诊断依据;远处转移才是恶性的证据.Ki-67和p53对患者的预后可能有指示意义.     

上皮样血管平滑肌脂肪瘤的临床病理特征

目的:探讨上皮样血管平滑肌脂肪瘤(epithelioid angiomyolipoma,EAML)的临床病理学特征.方法:回顾性分析17例病理诊断为EAML的组织学形态、免疫组织化学特点、临床及随访资料.结果:男5例,女12例,年龄21~62(平均31.2)岁,其中14例发生于肾脏(3例伴有子宫平滑肌瘤,2例伴有宫内孕);2例发生于肝脏,1例发生于腹腔;肿瘤最大径3~15 cm,镜下瘤细胞呈上皮样巢、片状分布,可见围绕血管呈放射状排列的结构;细胞体积大,卵圆形、梭形,胞质丰富,异型明显,核分裂少见,其中2例伴有出血、坏死.免疫组织化学HMB-45,Melan-A,SMA阳性,vimentin,ER和PR表达率分别为41%(7/17),23%(4/17)以及35%(6/17).17例EAML均行肿瘤根治或肿瘤切除术,术后随访5~52个月,1例2年后肝肺转移死亡,其余16例均健在,无复发及转移.结论:EAML多发生于女性,可能与激素水平有关;肾脏最常见,其次为肝、腹腔;病理形态多样,免疫组织化学对其诊断有重要价值,手术效果好,有转移可能.     

硬化型上皮样血管肌脂肪瘤

作者报道了2例罕见的上皮样血管肌脂肪瘤（AML），具有显著的硬化间质。2例中年女性患者，无结节性硬化症临床病史。例1发生在肾皮质，直径2cm，例2为肾旁腹膜后肿瘤，直径13cm。2个肿瘤由片状或巢状多角形上皮样或短梭形细胞组成，一致的圆形至卵圆形核，胞质嗜酸性，其间伴有束状透明变性的硬化性间质。例2肿瘤内有小区域看似成熟的脂肪细胞。免疫组化显示2例上皮样肿瘤细胞actin和desmin广泛阳性，MART-1阳性，2例硬化性间质束内有散在HMB-45阳性的细胞。而上皮样肿瘤细胞HMB-45实质上是阴性。作为上皮样血管肌脂肪瘤的亚型或硬化性血管周上皮样细胞肿瘤。作者报道的2例临床病理和免疫组化特征是相似的。     

上皮样血管平滑肌脂肪瘤7例临床病理分析

目的回顾分析上皮样血管平滑肌脂肪瘤(epithelioid angiomyolipoma,EAML)的形态学特点、免疫表型、诊断及鉴别诊断、临床特点及预后,加深对EAML的认识,提高诊断的准确性。方法观察7例EAML的病理形态学、免疫表型及临床特征。结果 7例EAML形态相似,肿瘤细胞体积大,呈卵圆形、梭形或多边形,胞质丰富,嗜酸性,细胞核大,大小不一,核仁明显,可见多核及巨核瘤细胞,有少数核分裂象,呈巢、片状分布,部分围绕血管呈袖套状。免疫表型:肿瘤细胞HMB-45、Melan-A、vimentin、SMA均弥漫阳性,EMA、CK、CD10均阴性。7例EAML均行肿瘤根治性手术或肿瘤切除术,术后随访3~56个月,除1例因有高度恶性十二指肠间质瘤病史于3个月后死于恶性间质瘤进展外,其余6例均健在,多次复查B超、CT等均无复发、转移。结论 EAML是具有恶性潜能的间叶源性肿瘤,病理形态学上易误诊为恶性肿瘤,免疫组化对鉴别诊断有重要的意义,目前手术治疗是主要方法,有复发或转移可能。     

上皮样血管平滑肌脂肪瘤6例临床病理分析

目的 探讨上皮样血管平滑肌脂肪瘤(epithelioid angiomyolipoma,EAML)的临床病理特点、免疫表型,诊断及鉴别诊断.方法 对5例肾脏和1例肝脏上皮样血管平滑肌脂肪瘤进行病理形态观察及免疫组织化学检测.结果 6例上皮样血管平滑肌脂肪瘤形态相似,肿瘤细胞多呈巢状和片状排列,围绕血管呈袖套状,瘤细胞体积大,形态单一,多边形或梭形,胞质丰富,嗜酸性颗粒状,细胞核较大,核仁明显呈空泡状.免疫组化显示肿瘤细胞HMB45、vimentin 和平滑肌特异性抗原(SMA,MSA)弥漫阳性;而EMA、CK(AE1/AE3)呈阴性.结论 上皮样血管平滑肌脂肪瘤是一种具有恶性潜能的间叶源性肿瘤,形态学上常容易误诊,免疫组化对鉴别诊断有重要意义.     

外阴孤立性纤维性肿瘤1例临床病理观察及文献复习

目的 探讨外阴孤立性纤维性肿瘤的临床病理学特点、免疫组化特征及鉴别诊断.方法 对1例外阴孤立性纤维性肿瘤进行组织学观察,行EnVision两步法免疫组化CD34、bcl-2、CD99、vimentin、CKpan、HMB-45、α-SMA、CD117、S-100蛋白、ER、PR、Ki-67染色及随访,并复习相关文献.结果 患者女,62岁.发现右侧外阴肿物4年余.眼观:肿瘤呈结节状,大小6 cm×5 cm×3 cm,切面灰白、实性,质韧.镜检:肿瘤由交替性分布的富于细胞和稀疏细胞区组成,梭形细胞呈束状、旋涡状或不规则状排列,部分与胶原纤维混杂,部分呈血管外皮瘤样结构.上皮样细胞有的围绕血管周围.细胞间细条索状、粗绳索样或疤痕样胶原纤维不规则性或石棉样的胶原物质沉积.瘤细胞CD34、bcl-2、CD99、vimentin均为阳性,CKpan、HMB-45、α-SMA、CD117、S-100蛋白、ER、PR均为阴性,Ki-67增殖指数<1%.结论 外阴孤立性纤维性肿瘤罕见,应与该部位相似形态的病变和血管外皮瘤样的肿瘤相鉴别.     

子宫血管周上皮样细胞肿瘤3例临床病理分析

目的探讨子宫血管周上皮样细胞肿瘤(perivascular epithelioid cell tumor,PEComa)的临床病理特征、诊断及鉴别诊断等。方法采用免疫组化EnVision两步法对3例子宫PEComa进行检测,并复习相关文献。结果3例肿瘤由梭形细胞和上皮样细胞构成,胞质透明至嗜酸性,间质血管丰富,其中1例肿瘤细胞异型性显著,并见出血、坏死。免疫表型:3例HMB-45阳性,2例SMA、Caldesmon阳性,Melan-A、TFE-3、desmin、CD10、CD117和S-100蛋白均阴性,Ki-67增殖指数5%~30%。随访4~55个月,患者均存活。结论子宫PEComa是一种少见的间叶源性肿瘤,结合组织学形态及免疫表型可辅助诊断。     

子宫体恶性血管周上皮样细胞肿瘤1例并文献复习

目的 探讨子宫体恶性血管周上皮样细胞肿瘤(perivascular epithelioid cell tumors,PEComa)的临床病理学特征、诊断及鉴别诊断.方法 采用免疫组化SP法对1例子宫体恶性PEComa进行免疫组化标记并复习相关文献.结果 患者扪及下腹部巨大肿块6个月,手术切除后11个月复发,CT示中下腹一巨大低-高密度混杂肿块.眼观:原发和术后复发肿瘤均体积巨大,切面为灰黄、灰红色,边界不清,质脆伴坏死.镜检:瘤细胞呈上皮样,胞质嗜酸性至透明,细胞异型性明显,可见明显核仁,未见核分裂.免疫组化:vimentin、HMB-45和Melan-A均(++),PNL2(|||),Ki-67增殖指数约3%,EMA、CK(AE1/AE3)、S-100、CD10、desmin、SMA和MSA均(-).结论 子宫体恶性PEComa十分罕见,需与子宫体恶性黑色素瘤、上皮样平滑肌肿瘤和横纹肌肉瘤相鉴别.     

Renal epithelioid angiomyolipoma with TFE3 gene amplification

目的 探讨伴有TFE3扩增的肾脏上皮样血管平滑肌脂肪瘤(epithelioid angiomyolipoma,EAML)的病理学特征、鉴别诊断及生物学行为.方法 对1例伴有TFE3扩增的肾脏EAML进行组织形态学观察、免疫组化染色及荧光原位杂交(fluorescence in situ hybridization,FISH)检测,追踪随访患者预后,并复习相关文献.结果 该例EAML呈片状弥漫分布,瘤细胞呈上皮样改变,细胞形态异型性较大,核分裂象易见.肿瘤侵犯包膜.瘤细胞表达SMA、TFE3、cathepsin K,TFE3基因出现多倍体扩增,未见易位发生.患者第一次手术3个月后肿瘤复发,术后半年腹腔肿瘤广泛侵犯、肺部见转移.结论 伴有TFE3扩增的EAML组织学形态及生长方式更具恶性特征,预后更差,与经典型EAML有所不同,需与其他形态学相似的肿瘤相鉴别.     

Renal epithelioid angiomyolipoma: Histopathologic review,immunohistochemical evaluation and prognostic significance

Epithelioid angiomyolipoma (EAML) is considered to be a potentially malignant tumor and requires a differential diagnosis from renal cell carcinoma. In this study, we assessed the clinicopathologic features of renal EAML and evaluated the prognostic significance. Among 78 angiomyolipoma (AML) patients, a total of 5 EAMLs were identified, accounting for 6.4% of the total AML cases. The mean age was 41.4 years, and the average tumor size was 12.7 cm in diameter. Association of tuberous sclerosis complex was identified in two cases. One EAML case showed malignant behavior with local recurrence and distant metastasis. The malignant EAML had a larger tumor size, a higher percentage of epithelioid component and atypical epithelioid cells, ≥2 mitoses per 10 high power fields with atypical mitosis, necrosis, extrarenal extension, and carcinoma‐like growth pattern. Furthermore, the malignant case revealed p53 immunoreactivity and decreased membranous E‐cadherin expression. Pathologic evaluation of adverse prognostic factors will be helpful for risk stratification and prognosis estimation of EAML patients.     

Renal epithelioid angiomyolipoma: a study of six cases and a meta-analytic study. Development of criteria for screening the entity with prognostic significance

Aims:  Renal epithelioid angiomyolipoma (EAML) is only described in case reports or in multi-institutional small series. The aim was to report cases seen at our institution and to perform a meta-analysis based on a literature review.
Methods and results:  Six EAML cases seen at our institution were reviewed and a meta-analysis performed using cases retrieved from a literature review. There were a total of 69 cases for review. The male:female ratio was 1:3. In the absence of areas of typical AML, useful features in distinguishing EAML from epithelial renal neoplasms include: extreme degree of cytological atypia, histiocytoid appearance, presence of melanocytic pigments, solid architecture with the absence of frequent areas of alveolar pattern, tubulo-papillary formation and scarring. A fatal outcome, distant or lymph node metastasis, venous invasion and local recurrence were considered as adverse events and occurred in 40% of cases over a period of follow-up of 3–60 months (mean 22.5 ± 18 months). Tumours with an unfavourable outcome showing marked cytological atypia and extensive tumour necrosis were larger (135 ± 43 mm) than those with a favourable outcome (79 ± 50 mm) ( P  < 0.002), and predominantly occurred in men.
Conclusions:  Renal neoplasms with certain unusual features should be investigated immunohistochemically to rule out the possibility of EAML. The frequency of adverse outcome is lower in EAML than in renal cell carcinoma.     

Epithelioid angiomyolipoma of kidney with atypical nuclear features and intranuclear inclusions on cytology

Described herein are the cytological findings of epithelioid angiomyolipoma (EAML) of the kidney with atypical nuclear features mistaken for renal cell carcinoma (RCC) in a 61‐year‐old male patient. Aspirates from this large renal mass were cellular and showed epithelioid cell clusters with focally crowded nuclei showing moderate anisonucleosis, small nucleoli, and prominent eosinophilic intranuclear inclusions. Failure to recognize the scanty adipose tissue component and preponderance of epithelioid cells with nuclear pleomorphism lead to a diagnosis of RCC on cytology. On histology, the tumor was essentially composed of epithelioid and spindle cells that showed the typical immunoprofile of an angiomyolipoma and only occasional foci of typical AML were seen. The hilar lymph node was involved in contiguity. However, in view of lack of obvious features of malignancy, the tumor was labeled as EAML with atypical features. Immunocytochemistry on the destained cytology aspirates revealed strong smooth muscle actin staining of all cells. To conclude, EAML can mimic a RCC. In such instances, lack of arborizing vasculature, absence of cytoplasmic fatty vacoulation, crowded nuclei with intranuclear inclusions, and lack of prominent nucleoli along with typical immunophenotype of EAML may assist in the cytology diagnosis. Diagn. Cytopathol. 2011;39:278–282. © 2010 Wiley‐Liss, Inc.     

Clinicopathologic features of renal epithelioid angiomyolipoma: report of one case and review of literatures

Epithelioid angiomyolipoma (EAML) is a rare renal mesenchymal tumor with malignant potential and is frequently associated with tuberous sclerosis complex (TSC). As metastasis of the tumor cells occur early, EAML is considered a potentially malignant tumor type and intrigues further research on it. Under the microscope, we could find the tumor was composed of atypical polygonal cells sheet mixed with classic angiomyolipoma (AML) components such as blood vessels with notable thick vascular walls, smooth muscle-like cells and adipocytes. Immunohistochemical studies showed that epithelioid cells were focally positive for vimentin, melanocytic markers (HMB-45), myoid markers (α-smooth muscle actin), CD34 and CD68; negative for cytokeratin, epithelial membrane antigen, CD10, and S-100. And the Ki67 index showed approximately 3%. Here, we report the morphological and immunohistochemical features of clinically or histologically malignant renal EAML and discuss its diagnosis, differential diagnosis and the prognosis.     

Epithelioid angiomyolipoma: a morphologically distinct variant that mimics a variety of intra-abdominal neoplasms

This review examines the histopathologic, immunohistochemical, ultrastructural, and molecular biologic features of epithelioid angiomyolipoma (EAML), with an emphasis on the differential diagnosis of intra-abdominal EAML. Epithelioid angiomyolipoma is an uncommon mesenchymal tumor with malignant potential, frequently associated with tuberous sclerosis complex. Histologically, EAML is characterized by sheets or nests of large polygonal epithelioid cells with abundant eosinophilic or occasionally clear cytoplasm, often with prominent nucleoli, and EAML may include multinucleated and markedly pleomorphic forms. As these tumors share a distinctive perivascular epithelioid cell phenotype, they belong to the PEComa tumor family. Nearly all EAMLs show immunoreactivity for both melanocytic and myoid markers. Ultrastructurally, EAMLs show evidence of melanogenesis by the presence of premelanosomes. Epithelioid angiomyolipoma can pose significant diagnostic challenges as it mimics morphologically a variety of neoplasms including renal cell carcinoma, renal oncocytoma, adrenal cortical neoplasm, epithelioid smooth muscle tumor, epithelioid peripheral nerve sheath tumor, epithelioid gastrointestinal stromal tumor, epithelioid melanoma, hepatoblastoma, and hepatocellular carcinoma. The variation in immunophenotype in these tumors requires a prudent use of immunohistochemistry, which may occasionally need complementation by electron microscopy to establish the correct diagnosis.     

Renal epithelioid angiomyolipoma with malignant features: Histological evaluation and novel immunohistochemical findings

Renal epithelioid angiomyolipoma (EAML) is a potentially malignant tumor type whose characteristics and biomarkers predictive of malignant behavior have not been elucidated. Here, we report three cases of renal EAML with malignant features but without histories of tuberous sclerosis complex. Case 1 involved a 29‐year‐old man with a 12‐cm solid mass in the right kidney who underwent radical right nephrectomy. Case 2 involved a 22‐year‐old woman with a retroperitoneal mass who underwent radical right nephrectomy and retroperitoneal tumorectomy. Local recurrence was detected 7 years post‐surgery. Case 3 involved a 23‐year‐old man with a 14‐cm solid mass in the left kidney who underwent radical left nephrectomy. Microscopically, the tumors in all cases demonstrated proliferation of epithelioid cells with atypia, mitotic activity, necrosis, hemorrhage, and vascular invasion. Epithelioid cells in all cases were immunohistochemically positive for melanocytic and myoid markers and weakly positive for E‐cadherin and β‐catenin. Immunohistochemistry revealed activation of the mammalian target of rapamycin pathway. Here, we report the morphological and immunohistochemical features of clinically or histologically malignant renal EAML.     

Immunohistochemistry of p53 and Ki-67 and p53 mutation analysis in renal epithelioid angiomyolipoma

Backgound: Renal epithelioid angiomyolipoma (EAML) is a rare variant of AML (angiomyolipoma) and is often associated with aggressive behaviors. The pathogenesis of EAML has been poorly understood. We analyzed the expression of p53 and Ki-67 by immunohistochemistry (IHC) and investigated p53 mutation analysis in 11 cases of EAML in comparison to classical AML. Methods: P53 and Ki-67 expression status were determined by IHC staining. P53 mutation analysis was performed using bi-directional sequencing. Results: Renal EAML tumors were significantly associated with more severe to moderate nuclear atypia (100% vs. 36.4%, P = 0.004) and mitotic activity (90.9% vs. 27.3%, P = 0.008) compared with AML tumors. Out of 11 cases of EAML, 8 were positive for p53. There was only 1 case with positive p53 expression in AML cases and expression of p53 protein showed significant difference between EAML and AML tumors (72.7% vs. 9.1%, P = 0.008). In addition, there were 7 AML and 6 EAML cases harbored P72R mutation (SNP) in exon 4 of p53. Compared with AML cases, 2 out of 11 cases of EMAL showed more than 10% positivity for ki-67. The finding of stronger p53 expression in renal EAML might have contributed to their malignant behavior. However, the abnormal p53 expression cannot be entirely explained by p53 mutations in the exons examined. Conclusions: Thus, the combination of immunohistochemical assessment of tumor antigens might improve our ability to predict the malignant outcome in EAML.     

肾脏上皮样血管平滑肌脂肪瘤的病理观察

目的对肾脏上皮样血管平滑肌脂肪瘤（epithelioid agiomyolipoma,EAML）的病理诊断、鉴别诊断和预后进行分析。方法2例肾脏EAML（其中1例为复发病例）,复习其临床资料,病理学检查包括常规病理学、免疫组织化学和超微结构,并进行随访。结果光镜下肿瘤均主要由具有多形性和不典型性的上皮样细胞组成,部分区域有明显的血管周上皮样排列;可见出血和坏死;并可见静脉内瘤栓;淋巴结内可见上皮样肿瘤细胞累及。免疫组织化学肿瘤细胞（包括淋巴结内肿瘤）HMB45、平滑肌肌动蛋白（SMA）、神经元特异性烯醇化酶（NSE）和波形蛋白弥漫阳性;S-100、melanpan和CD68散在阳性;而上皮细胞膜抗原（EMA）、AE1／AE3、CK7、CD117、肌肉特异性肌动蛋白（MSA）、结蛋白、白细胞共同抗原（LCA）、CD20、CIM5RO、CD30、CD15、嗜铬素（CgA）、突触素（Syn）、bcl-2、雌孕激素受体（ER、PR）和p53均为阴性。电镜检查可见一些肿瘤细胞内有黑色素小体样的致密颗粒、肌丝、密体,肿瘤细胞外可见不连续的基膜。2例患者手术后10个月状态良好,无肿瘤局部复发和转移征象。结论血管周上皮样排列、寻找经典血管平滑肌脂肪瘤的结构和肿瘤细胞表达HMIM5和SMA对于诊断和鉴别诊断至关重要。而细胞的不典型性、出血坏死和核分裂象可能只表明肿瘤的恶性潜能：淋巴结受累、肾静脉瘤栓不是恶性的诊断依据：只有远处转移才是恶性的证据。     

Renal epithelioid angiomyolipoma--a close mimic of renal cell carcinoma. Report of a case and review of the literature

The epithelioid variant of angiomyolipoma (EAML) is a rare tumor of unpredictable behavior that is composed of epithelioid, spindle, and giant cells and contains no or only a minimal amount of lipomatous tissue. The picture can lead to an erroneous diagnosis of renal cell carcinoma or sarcoma. We report on a case of EAML in the kidney of a 47-year-old female without any signs of tuberous sclerosis and review the literature. Grossly, a well-demarcated, spheroid, largely hemorrhagic tumor measuring 4.2 cm in diameter occupied the central third of the kidney. Histologically, it was solid, highly cellular, with occasional microcysts, composed of medium to large epithelioid cells with clear or oxyphilic cytoplasm, short spindle cells, and numerous giant multinucleated cells. After extensive sampling, adult-appearing fat tissue was found to present as rare foci of microscopic dimensions. Immunohistochemically, the tumor cells showed positive reactions with antibodies against HMB-45, melan A, CD-68, muscle-specific actin, and, rarely, smooth muscle actin. Cytokeratins and epithelial membrane antigen were negative. The EAML is a variant growing in a carcinoma-like pattern that can lead to an erroneous diagnosis of renal cell carcinoma. An extensive sampling and HMB-45 and CD-68 positivity combined with cytokeratin negativity are of paramount importance for the correct diagnosis. As a sporadic renal tumor it followed a benign course in most of the reported cases.