骨转移性小细胞癌11例穿刺病理的鉴别诊断

目的：探讨骨转移性小细胞癌穿刺病理的诊断与鉴别诊断,尤其是与骨原发Ewing肉瘤的鉴别诊断。方法收集11例骨转移性小细胞癌和20例骨原发Ewing肉瘤的临床病理资料,并采用免疫组化EnVision两步法检测两组病例中相关标志物的表达。结果11例骨转移性小细胞癌中,CD99阳性率27．3%,FLI-1阳性率54．5%;20例骨原发Ewing肉瘤中,CK阳性率15．0%。患者年龄、单发病灶、免疫组化标志物CK、vimentin、CD99、FLI-1、CD56的表达在两组间差异具有显著性。结论骨转移性小细胞癌与骨原发Ewing肉瘤的组织形态相似,免疫组化标志物的表达也有重叠,正确诊断需结合临床资料及免疫组化染色综合分析。     

大脑和脊髓原始神经外胚叶肿瘤临床病理学

目的：探讨原发于大脑和脊髓原始神经外胚叶肿瘤的临床病理特征、组织学发生及生物学行为。方法：采用组织病理学、免疫组化标记和电镜观察对１１例原发于大脑及脊髓的原始神经外胚叶肿瘤进行研究。结果：组织学特征为弥漫原始的小细胞,并形成Ｈｏｍｅｒ－Ｗｒｉｇｈｔ菊形团和明显的纤维组织分隔成小叶。免疫组化标记：ＮＳＥ阳性,Ｓｙｎ阳性,部分瘤组织中散在ＧＦＡＰ阳性。电镜：瘤细胞胞浆内可见致密核心的分泌颗粒。结论：该     

肋骨骨膜型尤文氏肉瘤／原始神经外胚叶瘤CT影像分析（附1例报道）

目的：探讨肋骨骨膜型尤文氏肉瘤（Ewing＇s sarcoma，ES）／原始神经外胚叶瘤（Primitive neuroectodermal tumor，PNET）的CT表现及临床病理特点。方法：经皮穿刺病理及免疫组化检查，结合CT扫描，证实肋骨骨膜型ES／PNET1例。结合文献复习，分析其CT表现及病理特征。结果：肋骨骨膜型ES／PNET的CT表现为肿瘤体积较大，密度不均，突向肺野内生长，瘤体内放射状或花瓣样骨膜新生骨或许是其特征性CT表现之一。结论：肋骨骨膜型ES／PNET临床罕见，恶性度高，其CT表现不典型，极易误诊。深入了解肋骨骨膜型ES／PNET的CT表现，对早期诊断、早期治疗具有重要价值。     

外周原始神经外胚叶瘤和尤文氏肉瘤的分子病理学新进展

外周原始神经外胚叶瘤和尤文氏肉瘤软组织和骨常见的高度恶性的肿瘤 ,两者密切相关 ,均属于PNET/EWS家族肿瘤。PNET/EWS携带特异性融合基因或其他复合物 ,可根据特异性分子基因病变对此类肿瘤进行诊断和鉴别诊断     

神经母细胞瘤骨髓转移23例临床病理分析

目的 探讨神经母细胞瘤骨髓转移的临床病理特征.方法 对23例神经母细胞瘤骨髓转移的临床病理资料进行分析,并做光镜观察及免疫组化染色.结果 神经母细胞瘤骨髓转移表现为微小浸润、中度浸润和弥漫浸润三种形式,主要根据骨髓造m组织与肿瘤成分的比例和分布而定,其中微小浸润常需行CgA/NSE免疫组化染色辅助诊断.结论 神经母细胞瘤骨髓转移的诊断需结合临床、光镜及免疫组化,以提高检出率并鉴别于横纹肌肉瘤、骨Ewing肉瘤、淋巴母细胞淋巴瘤/白血病.     

软组织小圆形细胞肿瘤的诊断与鉴别诊断(Ⅱ)

软组织小圆形细胞肿瘤是指光镜下形态近似的原始或较原始的小圆形细胞(部分呈类圆形或短梭形)组成的组织发生和生物学行为不同的一组恶性肿瘤.这组肿瘤涵盖的范围,各作者的意见尚不一致,一般认为软组织小圆细胞肿瘤主要包括外周性原始神经外胚瘤(pPNET)、骨外Ewing瘤、Askin瘤、胚胎性横纹肌肉瘤、促纤维性小圆细胞肿瘤、肾外横纹肌样瘤、圆形细胞脂肪肉瘤、神经母细胞瘤、小细胞低分化滑膜肉瘤、小细胞性间皮瘤、软组织淋巴瘤、粒细胞肉瘤和软组织转移性小细胞癌.上述肿瘤已在前文中[1]作了论述.从广义非传统上讲,另一类小细胞肿瘤大多发生在成年或老年,以内脏、皮肤为好发,但可发生在软组织或侵犯软组织.这些肿瘤具有分化差的特点,故光镜形态近似,免疫组化及超微结构等方面出现重叠现象,鉴别诊断有时十分困难.而区别这些形态近似的肿瘤,探讨其生物学行为具有较大的价值.现就其诊断和鉴别诊断加以叙述.     

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。     

鼻腔小细胞恶性肿瘤26例临床病理分析

目的 探讨鼻腔小细胞恶性肿瘤的病理形态学和免疫组化染色的特点.方法收集26例鼻腔小细胞恶性肿瘤,通过常规HE及免疫组化染色进行观察.结果 恶性黑色素瘤11例,可见突出的嗜酸性核仁、核沟、核内假包涵体,表达S-100蛋白、HMB-45、Melan-A.嗅神经母细胞瘤7例,可见神经原纤维、菊形团结构,NSE、Syn阳性,S-100蛋白在肿瘤周边的支持细胞中表达.横纹肌肉瘤4例,瘤细胞多嗜酸性,desmin、vimentin、MyoDl、Myogenin阳性.小细胞神经内分泌癌2例,可见较多的凋亡、坏死和出血,NSE、Syn、CgA均阳性.骨外Ewing肉瘤/原始神经外胚层肿瘤2例,可见Homer-Wright假菊形团及乳头状结构,CD99、vimentin、Syn、NSE均阳性.结论 鼻腔小细胞恶性肿瘤具有相似的临床和形态学表现,因此,只有根据其各自的形态学和免疫组化染色特点,才可做出正确的诊断及鉴别诊断.     

外周原始神经外胚叶瘤和尤因肉瘤染色体易位研究进展

染色体相互易位多见于骨和软组织肉瘤以及淋巴造血系统恶性肿瘤中．这些染色体易位导致多种分子水平上的异常．特别是融合基因的形成．被认为与肿瘤的发生有关。外周原始神经外胚叶瘤(peripheral primitive neuroectodermal tumors．pPNET)和尤因肉瘤(Ewing’s sarcoma．EWS)是软组织和骨常见的高度恶性肿瘤，两者关系密切，都有特征性     

胸膜肺母细胞瘤1例报道及文献复习

目的：阐明胸膜肺母细胞瘤的病理形态特征及鉴别诊断要点。方法：对1例小儿胸膜肺母细胞瘤进行了组织形态学,免疫组织化学分析。结果：胸膜肺母细胞瘤是一种纯间质性恶性肿瘤,好发于12岁以下的儿童及婴幼儿,起源于肺、胸膜或纵隔的原始细胞,镜下可见原始胚胎性的圆形或短梭形细胞,瘤细胞有呈巢趋势,酷似肾母细胞瘤,肝母细胞瘤等肿瘤原始胚基成分,免疫组化未见有上皮细胞及其他间叶成分标志的表达,另一种成分为梭形细胞,除表现为纤维肉瘤特点外,还向横纹肌肉瘤分化,结论：胸膜肺母细胞瘤是一种极为罕见的恶性肿瘤,应与肺母细胞瘤,原始神经外胚叶肿瘤及胚胎性横纹肌肉瘤等鉴别。     

石蜡包埋尤文瘤/外周原始神经外胚瘤中EWS-FLI1融合基因的表达

目的 运用逆转录聚合酶链反应(RT-PCR)技术检测石蜡包埋尤文瘤／外周原始神经外胚瘤(ES／pPNET)组织中特异性染色体易位融合基因EWS-FLI1／ERGmRNA的表达并探讨其诊断意义。方法 运用一步法RT-PCR技术检测25例石蜡包埋ES／pPNETs和15例其他小圆细胞肿瘤(包括8例胚胎型和腺泡型横纹肌肉瘤、4例低分化滑膜肉瘤、2例神经母细胞瘤和1例淋巴瘤)组织中EWS-FLI1／ERG的表达。结果 25例ES／pPNET中20例检测到EWS-FLI1／ERG融合基因的表达(8056),15例对照组均未检出EWS-FLI1的表达。结论 EWS-FLI1／ERGmRNA的表达是ES／pPNETs分子诊断的可靠指标,一步法RT-PCR是一种适用于临床常规石蜡包埋组织EWS-FLI1融合基因表达的检测方法。     

ZBTB16: A new biomarker for primitive neuroectodermal tumor element / Ewing sarcoma

Primitive neuroectodermal tumor (PNET) traditionally encompasses two different classes of tumors with similar morphology - PNET of the peripheral nervous system (pPNET) and PNET of the central nervous system (cPNET). The latter also includes germ cell tumor-derived PNET (gPNET). There are currently no specific markers for gPNET. This study seeks to investigate the expression of ZBTB16 in PNET and other small round blue cell tumors as well as its potential diagnostic utility. Immunohistochemical expression of the ZBTB16 was studied in a total of 27 PNETs (12 pPNETs, 8 cPNETs, 3 primary testicular gPNETs, and 4 metastatic gPNETs) and 38 small round blue cell tumors. Positive expression for ZBTB16 was seen diffusely in 9/12 (75%), moderately in 2/12 (17%) and focally in 1/12 (8%) of pPNETs, diffusely in 3/7 (43%) and moderately in 4/7 (57%) of gPNETs, and diffusely in 2/8 (25%), moderately in 2/8 (25%) and focally in 4/8 (50%) of cPNETs. Whereas, all of the 38 non-PNET small round blue cell tumors were nonreactive. The results suggest that ZBTB16 is a highly sensitive and specific biomarker for both pPNET and gPNET/cPNET. ZBTB16 effectively differentiates PNETs from other small round blue cell tumor mimics, including the two most common germ cell tumor-derived somatic malignancies - rhabdomyosarcoma and nephroblastoma. Of note, compared to the expression of ZBTB16 in pPNET/Ewing sarcoma and gPNET, the expression of ZBTB16 in cPNET was more variable, which appears consistent with the heterogeneity of cPNET. The close proximity of ZBTB16 and FLI-1 genes on chromosome 11q may explain the overexpression of ZBTB16 in PNET, especially in pPNET with t(1122) translocation.     

Extra-osseous Ewing sarcoma of the thyroid gland mimicking lymphoma recurrence: a case report

Extra-osseous Ewing sarcomas/peripheral primitive neuroectodermal tumors (EOES/pPNETs) are high-grade malignant tumors found in various organs, such as the lung, skin, intestine, kidney and female genital tract; however, to the best of our knowledge, only two cases have previously been identified in the thyroid gland. We describe a case of primary EOES/PNET of the thyroid gland in a 66-year-old man with a previous history of large B cell lymphoma. During a routine follow-up examination, the patient underwent an ultrasound cervical scan showing a solid nodule of the left thyroid lobe. The fine-needle aspiration biopsy of the nodule suggested a neuroendocrine tumor. Histological and immunohistochemical examination of the surgical specimen supported a diagnosis of EOES/PNET, which was further confirmed by the demonstration of EWSR1 gene translocation by means of fluorescent in situ hybridization and by the detection of glycogen particles and neurosecretory granules by means of electron microscopy. Total body computed tomography and magnetic resonance imaging excluded the involvement of other sites, and therefore a diagnosis of primary EOES/PNET of the thyroid gland was made.This paper also discusses the main differential diagnoses, including lymphoma recurrence, other small round cell tumors (primary or metastatic), and a thyroid localization of an EWS/PNET from another organ.     

Intracranial peripheral primitive neuroectodermal tumors of the cavernous sinus: a diagnostic peculiarity

Peripheral primitive neuroectodermal tumors (pPNETs) are aggressive, poorly differentiated neoplasms that occur in children and young adults. These tumors are associated with a peak incidence in the second decade and a slight male preponderance. Recently, Ewing sarcoma and pPNET tumors have been proven to carry identical translocations, the most common being t(11;22)(q24;q12). Intracranial Ewing sarcoma/pPNETs have rarely been described in the literature. We studied a case of intracranial pPNET arising in the right cavernous sinus of a 46-year-old man. On imaging, the tumor had both sellar and suprasellar components and was centered within the right parasellar region. Histologically, the tumor was composed of intermediate to large cells with round to oval hyperchromatic nuclei with distinct nucleoli. The cells contained a moderate amount of slightly basophilic cytoplasm. The tumor was markedly fibrotic and had collagen bands surrounding both individual and groups of cells. A large immunohistochemical panel was positive only for CD99 and vimentin. Fluorescence in situ hybridization did not show translocations associated with Ewing sarcoma/pPNET. However, a small percentage of these tumors can be negative for this translocation. In these cases, histology and immunohistochemical techniques in the absence of an alternative diagnosis are the only tools available to establish the diagnosis.     

Peripheral primitive neuroectodermal tumor/Ewing's sarcoma of the craniospinal vault: case reports and review

The peripheral primitive neuroectodermal tumor/Ewing's sarcoma family tumor (pPNET/ESFT) group includes small round cell tumors of the bone, soft tissue, and nerve with morphological attributes of the germinal neuroepithelium. Peripheral PNETs/ESFTs also occur within the craniospinal vault, a region including the central nervous system, the meninges, and the cranial and spinal nerve roots. Gene rearrangements between the EWS gene on chromosome 22q12 and members of the ETS gene family are common in and specific to pPNETs/ESFTs. Another defining characteristic of pPNETs/ESFTs is their membranous expression of the MIC2 gene product. We describe 2 cases of pPNETs within the craniospinal vault. An intradural tumor arising from the nerve roots of the cauda equina was discovered in a 32-year-old man presenting with radiculopathic back pain and lower-extremity weakness. An intracranial pPNET that mimicked a meningioma was found in a 21-year-old man presenting with headache and visual disturbances. MIC2 gene product expression and EWS/ETS gene rearrangement were detected in both case patients. The literature with regard to pPNETs/ESFTs arising within the craniospinal vault is reviewed.     

Primary vulvar Ewing's sarcoma/primitive neuroectodermal tumor in a post-menopausal woman: A case report

Ewing's sarcomas/peripheral primitive neuroectodermal tumors (ES/pPNETs) are high-grade malignant neoplasms rarely found outside the skeletal system. Only 12 cases of vulvar ES/pPNET have so far been reported, all involving children or women of child-bearing age. We describe the case of a 52-year-old woman who was admitted to our hospital for the local excision of a 4 cm vulvar mass, originally thought to be a Bartholin's gland cyst. It was subsequently found to consist of small round cells positive for anti-CD99 antibody, thus suggesting a diagnosis of ES/pPNET. The demonstration of EWSR1 gene translocations by means of fluorescent in situ hybridization excluded small-cell carcinoma, squamous cell carcinoma of the small type, Merkel cell carcinoma, and lymphoblastic lymphoma. After surgery, the patient received six cycles of polychemotherapy and radiotherapy; she is still alive and well after 1 year of follow-up. Our findings underline the crucial role of molecular biology techniques in the differential diagnosis of small round cell tumors in these unusual locations.     

Small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features of the thoracic wall: A case report with histological,immunohistochemical and ultrastructural examinations

A case of small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features is presented. The tumor was encountered in a 32 year old Japanese woman with an initial presentation of palpable tumor in the left lateral region of the thorax. The resected tumor was a partially well encapsulated whitish medullary one and consisted of small round and spindle tumor cells, together with so-called rhabdoid cells in the small round cell area. Although pseudorosettes were often observed, true rosette formation could not be detected anywhere. Ultrastructurally, despite a histologic variety of tumor cells, most tumor cells possessed numerous mitochondria, some of which occasionally contained abnormal filamentous or crystalloid structures. Various amounts of microfilaments were present in most tumor cells and microtubules were present in a few. A minority of small round cells possessed a small number of neurosecretory granules, especially in short cytoplasmic processes. A positive immunoreaction for neuron specific enolase was found by immunohistochemical examination in several small round tumor cells and for neurofilaments in lesser numbers. Despite the lack of S-100 protein, MB2 was detected in both small round and spindle cells. On the basis of these findings, the tumor of the present case corresponds to malignant peripheral nerve sheath tumor with neuronal differentiation and oncocytic features.     

Electron microscopy and other ancillary techniques in the diagnosis of small round cell tumors

The current study disusses a new approach to the group of small round cell tumors (SRCTs) independently of their primary anatomical location. We perform this analysis supported mainly by morphological means and particularly with the help of immunohistochemistry and electron microscopy; the last of which continues to play a decisive role in their differential diagnosis. The microscopical similarity of many of these tumors often makes the diagnosis in routine histology extremely difficult, due to the varying degree of heterogeneity present, and may have important therapeutic and prognostic implications. Thus a correct final diagnosis is mandatory for the clinic. Within the group of tumors that express a dominant or occasional small round cell pattern "SRCT" (neoplasms of the Central Nervous System excluded) are included: Ewing's sarcoma and peripheral neuroectodermal tumor (Es/pPNET) comprising its varieties, neuroblastoma, desmoplastic small round cell tumor, rhabdomyosarcoma, alveolar, solid and embryonal, small cell osteosarcoma, chondrosarcoma, myxoid and mesenchymal, round cell and myxoid liposarcoma, synovial sarcoma (monophasic undiffentiated), primitive malignant peripheral nerve sheath tumor (malignant small cell schwannoma), malignant non-Hogdkin lymphoma, Merkel cell tumor of the skin (small cell carcinoma including neuroendocrine carcinoma). This study discusses in each case not only the histology, supported by immunohistochemistry, but also the main ultrastructural characteristics. We are conscious that in some cases further cytogenetic or molecular biology support may be necessary, when considering the limits of morphology today. Thus, short references on molecular genetics, complementing the structural findings, are given.