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91.
To evaluate the accuracy and reproducibility of subgrouping and grading soft-tissue sarcomas by fine-needle aspiration biopsy (FNAB), a blind review was conducted of 84 FNAB specimens from 77 malignant and 7 benign soft-tissue lesions. Cytomorphologic subgroups included 31 spindle-cell, 24 pleomorphic, 11 myxoid, 7 epithelioid/polygonal, 3 small round cell, and 8 nondiagnostic cases. Malignancies included one lymphoma and 41 primary, 15 recurrent, and 20 metastatic soft-tissue sarcomas. Adequacy was defined as a majority of slides with at least 5 clusters of 10 unobscured cells. Five originally false-negative cases were considered nondiagnostic on review. Sarcoma was recognized in 59 of 64 adequate cases (92%) with available histology; however, the specific histopathologic subtype was identified in only 9 cases (14%). Benign myxoid and spindle-cell lesions were difficult to separate from low-grade sarcomas in 4 cases, and a B-cell lymphoma with sclerosis mimicked a low-grade myxoid sarcoma. The assigned cytologic grade accurately reflected the histologic grade in 90% of sarcomas when segregated into high and low grades. Pleomorphic, small round cell, and epithelioid/polygonal subgroups corresponded to high-grade sarcomas in all cases with only minor noncorrelations. Major grading noncorrelations occurred in 50% of myxoid and 9% of spindle-cell sarcomas. Therefore, attention should be given to specimen adequacy, and caution should be exercised when attempting to grade myxoid and spindle-cell sarcomas by FNAB.  相似文献   
92.
A rare case Is descrlbed of an Intramural sarcoma of the rlght common carotld artery coexistlng wlth adventitial inflammation and flbrosls, resembllng 'inflammatory aneurysm', which was resected from a 33-yearold Japanese woman who had presented with a pulsatile mass on the rlght side of the anterior neck. Grossly, the wall of the carotld artery showed an intimal tear with dlssectlon of the medla filled with thrombus. A graylsh area, abutting directly onto the dlssected space and Involving the media and inner adventltia, was composed of a-smooth muscle actin-positive and desmln-negative polygonal and splndle cells with large bluntended nuclei and coarse granular chromatin arranged Into a well-organized Interlacing bundle pattern. This portlon was thus considered to represent lelomyosarcoma. White to yellow-tan fibrotic tissue present in the adventitial area consisted of extensive lamellar fibrosis wlth scattered focl of lymphoplasmacytlc aggregates and obliterated arteries, and lacked atypical spindle and polygonal cells. These changes accorded with the histopathologlcal findlngs hitherto described in cases of 'inflammatory aneurysm', which is known to almost exclusively involve the abdominal aorta. We conslder this case unique In that the leiomyosarcoma involved an artery other than the aorta, wlth an 'inflammatory aneurysm'-like reaction in the same she. The posslble relatlonship between these two condltions Is dlscussed.  相似文献   
93.
Basement membranes were investigated in early angiomatous and late sarcomatoid stages of Kaposi's sarcoma (KS). Seven frozen skin biopsies of KS from five elderly Mediterranean people and one renal allograft recipient were labelled, using an immunoperoxidase technique, for basement membrane-specific macromolecules, laminin and type IV-collagen. Twenty-seven other frozen cutaneous lesions including haemangio and lymphangiosarcomas, benign vascular tumours, and various epithelial, melanocytic, fibrohistiocytic, fibrosarcomatous and muscular tumours were processed in the same way. In addition an ultrastructural study was performed in two cases of KS, one haemangiosarcoma and one lymphangiosarcoma. Intense labelling was observed for both type IV-collagen and laminin, which appeared closely co-distributed, in all areas of KS. Staining pattern was often regular and continuous around neoplastic vessels in early lesions of KS, as in benign vascular lesions, whereas in late nodular lesions large amounts of basement membrane components were present in intercellular spaces between densely aggregated spindle cells. In contrast, ultrastructural examination disclosed early disruption of basement membranes around neoplastic vessels, and occasional fragments of external lamina were seen at the interface between KS spindle cells and collagen. Similar results were obtained in angiosarcomas both by immunohistological and ultrastructural study. In the comparative group, laminin and type IV-collagen were present, in significantly fewer quantities and in various distinctive patterns, in epithelial, melanocytic, fibrohistiocytic and muscular tumors. This study deals with basement membrane modifications in early and late lesions of KS and provides further evidence in favour of the endothelial nature of the spindle cells of KS.  相似文献   
94.
本文旨在研究免疫组织化学在软组织肉瘤诊断、鉴别诊断的意义。判断肿瘤增生程度及预防 ,进展及治疗前景。  相似文献   
95.
Rosai Dorfman disease is rare benign disease of phagocytic histiocytosis usually present as painless massive lymphadenopathy. Extra nodal presentation of Rosai Dorfman disease is rare but also described. We hereby describe an unusual presentation of the extra nodal Rosai Dorfman disease with rapidly growing soft tissue lesion in the left thigh with associated osseous lesions in the right distal femur, left distal femur, left proximal tibia and presence of solitary pulmonary nodule. This case is unique as clinical presentation highly suspicious of soft tissue sarcoma but excision biopsy of thigh lesion showed Rosai Dorfman disease.Though RDD in extremities has been described in limited number of cases, to the best of our knowledge this is first case of lower extremity RDD associated with osseous lesions and pulmonary nodule but without lymphadenopathy.  相似文献   
96.
BackgroundPrior studies evaluating the impact of adjuvant or neoadjuvant radiation on clinical outcomes of patients with non-lipomatous retroperitoneal sarcoma have been underpowered.MethodsWe queried the National Cancer Database to identify patients undergoing surgical resection of retroperitoneal sarcoma with non-lipomatous histology from 2004 to 2016. Multivariable logistic regression and Cox proportional hazards modelling with patients stratified by tumor size were used to identify factors associated with overall survival.Results3,394 patients met inclusion criteria. 592 had small (<5 cm), 1,186 had intermediate (5–10 cm), and 1,616 had large (>10 cm) tumors. Use of either neoadjuvant or adjuvant radiotherapy was associated with improved survival for patients with intermediate (neoadjuvant HR 0.67, CI [0.46, 0.98]; adjuvant HR 0.61, CI [0.50, 0.76]) and large (neoadjuvant HR 0.50, CI [0.37, 0.68]; adjuvant HR 0.56, CI [0.47, 0.69]) tumors, while adjuvant radiation therapy was associated with a survival benefit for small-sized tumors (HR 0.67, CI [0.46, 0.99]).ConclusionsRadiation therapy is associated with an overall survival benefit in patients presenting undergoing resection of non-lipomatous retroperitoneal sarcoma.  相似文献   
97.
IntroductionKaposi’s sarcoma (KS) remains the most frequent malignancy in persons living with HIV (PWH) in Latin America. We examined KS trends and outcomes from Latin American clinical sites in the era of increased access to antiretroviral therapy (ART).MethodsCohorts in Brazil, Peru, Mexico, Honduras, Argentina and Chile contributed clinical data of PWH ≥16 years old from 2000 to 2017, excluding patients with KS diagnosed before clinic enrolment. We compared KS incidence over time using multivariable incidence rate ratios. Predictors of KS before/at or after ART initiation and of mortality after KS were examined using Cox regression.ResultsOf 25 981 PWH, 481 had incident KS, including 200 ART‐naïve and 281 ART‐treated patients. From 2000 to 2017, the incidence of KS decreased from 55.1 to 3.0 per 1000 person‐years. In models adjusting for CD4 and other factors, the relative risk for KS decreased from 2000 to 2008. Since 2010, the adjusted risk of KS increased in the periods before and ≤90 days after ART initiation but decreased >90 days after ART. In addition to low CD4 and male‐to‐male sex, KS risk after ART was associated with age and history of other AIDS‐defining illnesses. Mortality after KS (approximately 25% after five years) was not associated with either year of KS diagnosis nor timing of diagnosis relative to ART initiation.ConclusionsKS incidence in Latin America has remained stable in recent years and risk is highest before and shortly after ART initiation. Early diagnosis of HIV and ART initiation remain critical priorities in the region.  相似文献   
98.
小鼠树突状细胞肉瘤细胞系的建立及形态学鉴定   总被引:5,自引:1,他引:5  
李存玺  顾蓓 《解剖学报》1997,28(1):63-68
本研究目的是建立鉴定树突状细胞肉传代细胞系,即荷LII瘤615鼠脾脏进行原代细胞培养,经传统代培养后新建立一株体外传代细胞系,经鉴定为树突状细胞肉瘤细胞系,命名为DCS。该细胞体外呈分支状。酶组织化学检查发现碱性磷酶酶、酸性磷酶酶、1非特异性脂酶、过氧化酶及胞膜ATPase均阴性。  相似文献   
99.
乌索酸对S-180肉瘤小鼠的抑瘤作用及其机制   总被引:2,自引:0,他引:2  
目的:研究乌索酸(UA)对S-180肉瘤小鼠抑瘤作用及其可能机制。方法:建立小鼠S-180肉瘤模型,以灌胃方式给药。乌索酸连续灌胃治疗9 d,测量体质量、瘤重、脾重;计算抑瘤率及脾指数;光镜下观察组织结构的变化;流式细胞仪检测乌索酸对肉瘤鼠免疫功能、细胞周期和细胞凋亡的影响。结果:乌索酸对S-180肉瘤小鼠抑瘤率为62.82%,脾指数较生理盐水组增加。光镜下可见大片坏死及凋亡细胞。流式细胞仪分析显示乌索酸具有调节免疫功能的作用;使肿瘤细胞阻滞在S期;肿瘤细胞凋亡率达到24.17%。结论:乌索酸可显著抑制肿瘤生长,其抗肿瘤机制可能与提高机体免疫功能、肿瘤细胞S期阻滞及诱导其凋亡有关。  相似文献   
100.
对16例尤文肉瘤作临床病理回顾。本组年龄平均17.4岁,男女比例为4.3:1。2/3见于长骨,股骨最多,次为盆骨。病程平均9.5月。最常见的症状是疼痛,其次是肿块,发热一般为低中度热,WBC轻度升高。巨检肿瘤自髓腔经骨皮质浸润软组织,鱼肉状,常见出血坏死。镜下为密集、一致的小圆细胞;纤维组织小梁和形成的不规则小叶;常见假菊团以及出血坏死。本组诊断及治疗大多己属晚期,预后很差,约83%病例1年内死亡。建议重视临床、X光和病理三方面相结合,使本病获早期诊治。  相似文献   
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