肾恶性横纹肌样瘤15例临床病理及免疫组织化学分析

报道１５例肾恶性横纹肌样瘤（ＭＲＴＫ）的临床病理及免疫组化特点。男女之比为２．８：１。年龄４个月至４岁７个月，平均１岁零６个月。随访１０例，８例均于术后半年内死１０亡，２例健在。典型组织学改变为细胞弥漫排列，多边形，胞浆丰富嗜酸性，核仁突出。部分细胞胞浆内有嗜酸性包涵体，部分病例可见上皮样排列，间质硬化及梭形细胞成分。免疫组化显示１５例Ｖｉｍｅｎｔｉｎ（＋），１２例ＥＭＡ（＋），８例Ｃｙｔｏｋｅｒａｔｉｎ（＋）。结果提示，本瘤是一种好发于婴幼儿、预后差、多表现型的恶性肾肿瘤。可能来源于某种具有双向分化能力的多潜能细胞。     

多囊性肾透明细胞癌的病理学诊断

目的：探讨多囊性肾透明细胞癌的临床病理特点。方法：对1例多囊性肾透明细胞癌进行了免疫组化染色,并进行文献复习。结果：本例右肾肿物18年。大体见肿物由多发不等的囊腔组成。镜下囊内壁主要由单层立方或柱状上皮被覆,部分为多层并有乳头形成。瘤细胞胞质透亮,无明显异型性。癌细胞免疫表型cytokeratin、CEA和vimentin呈阳性表达。本例诊断为多囊性肾透明细胞癌。结论：多囊性肾透明细胞癌是一种罕见的肾癌病理类型。临床上主要采用根治切除术。本瘤的生物学行为属于低度恶性肿瘤。     

胰腺囊性-实性肿瘤的临床病理诊断

目的：探讨胰腺囊性－ 实性肿瘤临床病理、免疫组化特点、组织发生及生物学行为。方法：对２ 例胰腺囊性－ 实性肿瘤进行光镜观察及免疫组化染色。结果：２ 例均为年轻女性（２１ 岁和３５ 岁）。肿物为半囊半实性。ＨＥ染色片中瘤细胞大小形态较一致,核圆形或卵圆形,核异型性不明显,核分裂象罕见。肿瘤细胞围绕纤维血管复层排列形成假乳头突起为其特征。免疫组化染色显示α１ＡＴ、ＥＲ和ＰＲ均阳性,ＣＥＡ、Ｓ１００ 、ＮＳＥ均阴性。随访：１ 例带瘤生存２ 年后死亡,１ 例术后９ 个月健在。结论：胰腺囊性实性肿瘤可能来源于腺泡细胞,为性激素依赖性肿瘤,具有侵袭性行为,是一种低度恶性肿瘤。     

肾透明细胞肉瘤的临床病理及免疫表型特征

目的 探讨肾透明细胞肉瘤（clear cell sarcoma of the kidney,CCSK）的临床病理特点、免疫表型特征及鉴别诊断。方法 应用HE和免疫组化vimentin、bcl-2、desmin、S-100蛋白、CD99、CD34、CDll7、CK、EMA染色,观察2例CCSK的病理组织学形态,并复习文献。结果 镜下见瘤细胞为上皮样或短梭形,被分枝状纤维血管间质分隔成巢团状,部分区域见黏液样变性微囊肿和细胞外胶原玻璃样变类似骨样组织的硬化型等形态变异。免疫组化示：瘤细胞vimentin和bcl-2弥漫阳性,余为阴性。结论 CCSK是一种罕见的儿童期恶性肾肿瘤,诊断主要依靠组织病理学和免疫组化,熟悉其形态学变异有利于与其它类似病变如肾母细胞瘤、先天性中胚叶肾瘤、肾恶性横纹肌样瘤、原始神经外胚叶肿瘤等鉴别。     

肾上腺肌纤维母细胞瘤

目的：观察肌纤维母细胞瘤形态及免疫组化特点。方法：对１例儿童肾上腺的肌纤维母细胞瘤进行光镜观察和免疫组化染色。结果：ＨＥ中瘤细胞呈梭形、不规则形，排列无序，间杂以淋巴细胞等浸润及胶原纤维束；免疫组化显示瘤细胞Ｖｉｍ（＋），ＳＭＡ＋（＋），ＣｇＡ（－），ＥＭＡ（－）。手术彻底切除肿瘤后，患者临床症状消失。结论：肌纤维母细胞瘤是由既具有平滑肌细胞特征，又具有纤维母细胞特征的独立性肿瘤。     

肾脏原发性孤立性纤维性肿瘤3例报道并文献复习

目的 探讨肾孤立性纤维性肿瘤(solitary fibrous tumor,SFT)的临床病理学特征、诊断、鉴别诊断及预后.方法 对3例罕见的肾SFT进行临床、病理组织学形态观察及免疫组化染色,并复习相关文献.结果 原发于肾脏的SFT临床与影像学检查结果缺乏特征性表现,镜下细胞形态基本为长梭形,部分为卵圆形或上皮样细胞.其主要特点为含丰富的胶原纤维和形成多量瘢痕.免疫组化染色示瘤细胞CD34和CD99均(+),BCL-2(±).结论 发生于肾脏的SFT较为罕见,因缺乏特异性的术前诊断依据而极易误诊,确诊需依赖病理学检查,免疫组化染色有助于诊断及鉴别诊断.     

肾肉瘤样癌5例临床病理分析

目的：观察肾肉瘤样癌形态特征。方法：５例肾肉瘤样癌进行光镜观察及免疫组化染色。结果：以肉瘤样成分为主３例，血管外皮瘤样为主１例及破骨细胞瘤样巨细胞瘤１例，５例肉瘤样成分角蛋白阳性，４例波形蛋白阳性。结论：肾肉瘤样癌的形态特征为癌细胞具有双重分化，具有向间叶性肿瘤转分化的过渡方式。     

肾脏黏液样小管状和梭形细胞癌临床病理分析

目的探讨肾脏黏液样小管状和梭形细胞癌（mucinous tubular and spindle cell carcinoma, MTSCCa）的临床病理特征和鉴别诊断要点及生物学行为。方法对4例MTSCCa标本进行组织病理学和免疫组化染色观察，并复习临床资料及相关文献。结果该肿瘤好发于女性，发病年龄17～82岁（平均53岁），临床症状不明显。组织学：肿瘤与周围肾组织分界清楚，切面实性、灰白色，肿瘤细胞形态呈双相（小管状和梭形细胞）或三相（小管状、梭形和脊索瘤样或黏液样）。其他组织学表现：泡沫样巨噬细胞聚集、典型的透明细胞和乳头状或乳头结构。免疫组化显示复合性免疫表型。结论MTSCCa是一种罕见的低级别多形性肿瘤，组织学谱系在不断扩大，免疫组化表型及组织学形态与乳头状肾细胞癌（PRCCa）有重叠。     

肾嗜酸细胞腺瘤临床病理学分析

目的探讨肾嗜酸细胞腺瘤的临床病理特征和鉴别诊断。方法分析8例肾嗜酸细胞腺瘤临床资料及组织病理学和免疫表型特点,按WHO(2004)肾细胞肿瘤分类标准重新阅片分类。结果CT增强扫描后肿瘤密度均匀一致,瘤体中央可见星状低密度区是该瘤的主要特征。病理组织学:肉眼观察肿瘤质均,无坏死、呈棕红色,部分肿瘤有中心瘢痕;光镜下胞质强嗜酸性,粗颗粒,巢状或实片状排列,无坏死,无核分裂象或核分裂象罕见;免疫组化:CK8阳性,vim-entin阴性。结论肾嗜酸细胞腺瘤是一种肾脏良性肿瘤,CT影像特征有助于术前诊断。根据其组织学及免疫组化标记,可与胞质嗜酸性肾癌鉴别。     

胰腺囊实性肿瘤的免疫组化及超微结构观察

目的：了解胰腺囊实性肿瘤的免疫组化及超微结构特点。分析其临床病理特点与预后的关系。方法：用HE、过碘酸雪夫（PAS）和免疫组化（S-P法）及电镜观察7例胰腺囊实性肿瘤。结果：肿瘤较大，包膜较完整，囊实相同，显微镜观察HE染色片中瘤细胞大小形态较一致。核圆形或卵圆形，核异型不明显，核分裂象罕见，肿瘤细胞围绕纤维血管复层排列形成假乳头片中瘤细胞大小形态较一致。核圆形或卵圆形，核异型不明显，核分裂象罕见，肿瘤细胞围绕纤维血管复层排列形成假乳头突起为其特征。免疫表型，波形蛋白2例表达阳性，低分子量角蛋白6例为阳性，突触素4例为阳性，α1-AT6例阳性，胰岛素2例阳性，高分子量角蛋白，上皮膜抗原，生长抑素均为阴性，超微结构观察，4例瘤细胞分化良好，有数个细胞内含有类似酶原颗粒小体，直径0.8-1.2μm，有界膜，电子密度不均。结论：胰腺囊实性肿瘤可能起源于胰腺腺泡又具有内分泌特征，临床经过表现为良性，预后良好。     

Differentiated papillary kidney tumors. Differentiation between metanephric adenoma and papillary adenoma

Metanephric adenoma of the kidney is a well described tumor entity. The differential diagnosis between papillary adenoma or papillary carcinoma type 1 and metanephric adenoma of the kidney can be challenging in single cases. We report two cases of metanephric adenomas and compare their immunophenotype with a papillary adenoma. The analysis of these metanephric adenomas and a review of the literature shows that CD-57 positivity and lack of EMA expression are helpful in distinguishing metanephric adenoma from papillary adenoma and papillary carcinoma. Glomeruloid structures, Psammoma bodies, necrosis or expression of cytokeratin 7 and vimentin are common features in metanephric adenoma and papillary adenoma or papillary carcinoma. The knowledge of the immunohistochemical constellation is important, because metanephric adenoma can be very large and often have some necrosis.     

Metanephric adenoma-like tumors of the kidney: report of 3 malignancies with emphasis on discriminating features

BACKGROUND: Metanephric adenoma is a very rare benign renal tumor; only 80 well-documented cases have been reported to date. We have seen several renal tumors that were originally incorrectly diagnosed as metanephric adenoma. DESIGN: We present 3 unusual renal tumors (2 primary and 1 metastatic), each of which illustrates important pathologic features useful in discriminating metanephric adenoma from malignant mimics. RESULTS: Case 1 involved a 46-year-old man with multiple small, cortical, solid, papillary (chromophil) renal cell carcinomas in his right kidney; the patient developed multiple, histologically identical, solid, papillary (chromophil) carcinomas in the opposite kidney 17 months later. Case 2 involved a 32-year-old woman with a 14-cm right renal tumor who developed soft tissue and bone metastases over a 17-year period. Case 3 involved a 52-year-old woman who presented with a 1.8-cm corticomedullary renal nodule, which eventually proved to represent a metastasis from a poorly differentiated (insular) carcinoma of the thyroid. All 3 tumors superficially resembled metanephric adenoma and consisted of primitive, dark-staining cells arranged in tubules or sheets. Each tumor, however, also had features inconsistent with the diagnosis of metanephric adenoma, including multifocal lesions with a variable nuclear-cytoplasmic ratio and diffuse cytokeratin 7 and epithelial membrane antigen immunopositivity in case 1, a 14-cm-diameter tumor with occasional mitoses in case 2, and a distinct fibrous capsule with capsular and vascular invasion in case 3. In addition, all 3 tumors lacked the cytologic features of bland overlapping nuclei with imperceptible cytoplasm consistently seen in metanephric adenoma. CONCLUSION: Adherence to strict histopathologic criteria will discourage misdiagnosis of a malignant or potentially malignant renal neoplasm as the rare and always benign metanephric adenoma.     

Multifocal metanephric adenoma in childhood

Metanephric adenoma is the most commonly occurring member of the metanephric tumor family, which also includes metanephric adenofibroma and metanephric stromal tumor. According to the World Health Organization classification, however, it is not commonly multifocal. Reported herein is the case of a 9-year-old boy with multifocal metanephric adenoma. Histologically, surgical sections showed multifocal proliferation of small rounded and uniform cells with smooth nuclear contours, scant pale-staining cytoplasm, dark-staining nuclei, and inconspicuous nucleoli: the cells were arranged in sheets and acinal, ductal, glomeruloid, and papillary structures. On immunohistochemistry the tumor cells were positive for vimentin, cytokeratins (CAM5.2, AE1/AE3, and CK18), and WT1, but negative for cytokeratin 7 (CK7) and epithelial membrane antigen (EMA). The Ki-67 labeling index was <1%. In addition, cytogenetic analysis indicated a normal karyotype (46XY). Other histologically similar tumors are papillary renal cell carcinoma and nephroblastoma, and it is necessary to distinguish metanephric adenoma from those tumors because of malignancy. In contrast to those tumors, metanephric adenoma has inconspicuous nucleoli, loss of CK7 and EMA expression, and no mitotic figures. Thus, the histological and immunohistochemical features of the present case were compatible with metanephric adenoma.     

Metanephric adenoma of the kidney with massive hemorrhage and necrosis: immunohistochemical, ultrastructural, and flow cytometric studies

Metanephric adenoma of the kidney is rare. We report 2 cases of metanephric adenoma with massive hemorrhage and necrosis. Case 1, a 42-year-old Japanese woman, complained of abdominal pain. Case 2, a 41-year-old Japanese woman, complained of fever and lumbago. They underwent nephrectomy. The cut surface was solid and yellow with massive hemorrhage and necrosis. These tumors showed packed tubular and glomeruloid patterns. The tumor cells were uniform and small, with uniform, oval, and hyperchromatic nuclei and scant cytoplasm, and showed reactivity for cytokeratin, vimentin, and CD 57. The MIB-1 indexes were up to 0.63%. The DNA ploidy pattern was diploid. The tumor cells formed small tubular structures with lumina and microvilli. These features suggested that metanephric adenoma is a benign tumor of an immature epithelial nature.     

Embryonal adenoma of the kidney: A report of two cases

Embryonal (metanephric) adenoma of the kidney, like Wilms' tumor, exhibits small monomorphic, blue cells arranged as vague, tubular rosettes. Unlike Wilms' tumor, which requires chemotherapy or multi-modality therapy for optimal management, the available evidence indicates that embryonal adenoma is most likely cured by simple enucleation or nephrectomy. Two women, age 54 (Case 1) and 78 (Case 2), respectively, underwent needle biopsy for a radiologically well circumscribed renal lesion with associated hematuria. The cellular smears contained vague rosette-like arrangement of small, blue cells with scant cytoplasm and evenly distributed, fine, nuclear chromatin. In cell blocks, these cells were arranged as compact, primitive, tubular rosettes or rare, more-solid clusters. Assuming that the absence of undifferentiated blastema and primitive glomeruli represented a sampling error, a diagnosis suggesting of Wilms' tumor was made in Case 1. At nephrectomy, despite extensive sampling, the typical triphasic Wilms' morphology and anaplastic or necrotic areas were not seen. In the presence of architectural monotony, the diagnosis in Case 1 was amended to embryonal adenoma. Case 2 was cytologically diagnosed as embryonal adenoma of the kidney and is being followed conservatively. In our opinion, the presence of monotypic architecture at cytology/histology is very helpful in differentiating renal embryonal (metanephric) adenoma from Wilms' tumor. Diagn. Cytopathol. 16:42–46, 1997. © 1997 Wiley-Liss, Inc.     

S100 protein expression distinguishes metanephric adenomas from other renal neoplasms

Metanephric adenoma is a benign renal neoplasm with morphologic features similar to those of malignant renal neoplasms, such as papillary renal cell carcinoma (RCC) and Wilms' tumor. Different methods have been used to distinguish between metanephric adenoma and papillary RCC and Wilms' tumor. However, some techniques are not always available, such as certain immunohistochemical stains, cytogenetics, molecular genetics, and electron microscopy. In the current study, we compared the expression of S100 protein in 15 cases of metanephric adenoma, 10 cases of Wilms' tumor, and 13 cases of papillary RCC. Our results revealed strong expression of S100 proteins in all cases of metanephric adenoma, weak expression in two cases of Wilms' tumor, and no expression in any of the cases of papillary RCC. These findings indicate that S100 could be a useful and accessible tool for the diagnosis of metanephric adenoma.     

Fine‐needle aspiration of metanephric adenoma of the kidney with clinical,radiographic and histopathologic correlation: A review

Metanephric adenoma of the kidney is an uncommon benign epithelial neoplasm with only a small number of reports that describe its cytologic features. We describe two additional cases of metanephric adenoma diagnosed on fine‐needle aspiration biopsy and review the available literature. Our cases showed similar cytology and were composed of cellular smears with numerous clusters of small, oval to round cells arranged in a microfollicular pattern and papillary configurations. The tumor cells had scant cytoplasm, fine chromatin and absent nucleoli. Psamomma bodies, nuclear atypia, cellular cpleomorphism, necrosis, and mitoses were absent. Because of the rarity of this tumor and the common cytologic features it shares with other lesions, including malignant tumors such as Wilms’ tumor and papillary renal cell carcinoma, awareness of the cytologic features of metanephric adenoma may aid in avoiding a diagnosis of malignancy, especially preoperatively, and in guiding the proper management for the patients. Diagn. Cytopathol. 2013;41:742–751. © 2013 Wiley Periodicals, Inc.     

Production of erythropoietin and multiple cytokines by metanephric adenoma results in erythrocytosis

This is the first report of direct evidence that metanephric adenoma cells produce erythropoietin and other types of cytokines, which may be the cause of the high incidence of erythrocytosis in patients with this tumor. The purpose of the study was to establish a metanephric adenoma cell line in vitro from nephrectomized tumor tissue in order to investigate the ability of metanephric adenoma cells to produce erythropoietin and other types of cytokines. The tumor tissue was obtained from a 16-year-old boy who had developed metanephric adenoma with erythrocytosis and was served for cell culture. Significantly high concentrations of erythropoietin, granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte-colony-stimulating factor (G-CSF), interleukin-6 (IL-6), and IL-8 were detected in the cell culture supernatant. Southern hybridization showed specific positive signals for GM-CSF, G-CSF, IL-6, IL-8 and erythropoietin. The number of chromosomes was 46-XY without any structural abnormalities in cytogenetic analysis of the cultured cells.     

Diagnosis of renal metanephric adenoma: relevance of immunohistochemistry and biopsy

Most renal tumors of the adult are carcinomas. Their treatment is surgical, consisting of limited excision or nephrectomy. In some instances, biopsy of the tumor can be performed in order to adapt treatment. We report the case of a 45 year-old woman presenting with renal tumor. A biopsy of the mass showed a metanephric adenoma. No surgical excision was performed because of the benignity of this tumor. Here we develop the interest of immunohistochemistry for differential diagnosis of metanephric adenoma and other "basophilic small cell tumors" of the kidney. We also put the stress on the growing role of biopsy of renal tumor allowing optimal treatment.     

Metanephric adenoma lacks the gains of chromosomes 7 and 17 and loss of Y that are typical of papillary renal cell carcinoma and papillary adenoma.

Metanephric adenoma has morphologic similarities to papillary renal cell neoplasms. Cytogenetic studies of papillary renal cell carcinoma and papillary adenoma have shown frequent gains of chromosomes 7 and 17 and loss of the Y chromosome. Some cytogenetic studies have supported the hypothesis that metanephric adenoma is related to papillary renal cell neoplasia; others have not. Seven metanephric adenomas were studied with fluorescence in situ hybridization in paraffin sections using centromeric probes for chromosomes 7, 17, and Y diluted 1:100 with tDenHyb1 buffer. The signals in 100 to 200 nuclei were counted in each tumor. Samples of histologically normal renal cortical tubule epithelium were used as controls. In all seven metanephric adenomas, the results for chromosomes 7 and 17 were similar: a high percentage of nuclei with two signals (range, 75 to 85%; median, 79%). Normal kidney showed similar results (range, 78 to 88%; median, 84%). The Y chromosome was present in all three of the tumors from males (range, 86 to 89% of nuclei; median, 87%). Normal kidney gave similar results (range 82% to 91%, median 84%). The presence of chromosomes 7, 17, and Y in metanephric adenomas is similar to their presence in normal kidney. Metanephric adenoma lacks the frequent gains of chromosomes 7 and 17 and losses of the Y chromosome that are typical of papillary renal cell neoplasms, supporting the notion that metanephric adenoma is not related to papillary renal cell carcinoma and papillary adenoma. Genetic analysis of chromosomes 7, 17, and Y may facilitate discrimination of metanephric adenoma from papillary renal cell carcinoma in difficult cases.