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51.
60 intracranial tumors have been studied immunohistochemically to determine the proliferation rate by staining for the monoclonal antibody KI-67, which recognizes a nuclear antigen expressed by cells in proliferation. In gliomas a clear correlation of stained nuclei to the histologically determined degree of malignancy was found: slow growing astrocytomas and oligodendrogliomas had an average proliferation rate of 1%, more malignant forms of 7–10%. Glioblastomas were found to have a growth fraction of 15%. Metastases had an even higher rate of 20% proliferating cells. In meningiomas the proliferation rate was mainly about 1%, but in three cases it was between 5% and 7%. Whether this is indicative for a higher risk of tumor recurrence, remains to be correlated to the clinical course. Hemangiopericytomas had a proliferation rate of 9% and 16%, respectively, the latter recurring within four months. It may be concluded from the results of this study, that investigation of intracranial tumors with KI 67 may be of prognostic value and can possibly contribute to an individualized tumor therapy.  相似文献   
52.
对11例手术病理证实的椎管内肿瘤进行磁共振成像(MRI)增强扫描的前、后分析,并对肿瘤定位、定性和鉴别诊断作了初步探讨。根据肿瘤形态、边界、强化程度,及与脊髓、硬脊膜、神经根等关系,MRI的增强扫描对提高其定位、定性诊断均有较大的帮助。  相似文献   
53.
Fluid-fluid levels in cavernous hemangioma of soft tissue   总被引:3,自引:0,他引:3  
Five cases of cavernous hemangioma with fluid-fluid levels on magnetic resonance imaging and/or computed tomography are reported. The signal characteristics were those of blood and histological analysis of the fluid-fluid levels showed that they were blood-filled cavities in the tumor. Although this finding itself is not specific, it may help in confirming the diagnosis of cavernous hemangioma.  相似文献   
54.
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies. Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor, although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value of the endoscopic appearance was superior to endoscopic biopsy in this series. Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003. Supported by FADA-CAPES/PROP 200J (M.L.D.).  相似文献   
55.
超声心动图诊断原发性心脏肿瘤   总被引:1,自引:1,他引:0  
目的:探讨原发性心脏肿瘤超声心动图(ECG)特征。方法:利用ECG检查42例心脏肿瘤。其中粘液瘤38例,恶性肉瘤2例,均经手术病理证实。横纹肌瘤2例,经随访证实。结果:ECG对38例粘液瘤,2例横纹肌瘤全部做出正确诊断。2例恶性肿瘤提示相应部位占位病变。粘液瘤多发生在左房,有明确的瘤蒂,肿瘤回声稀疏,活动度大。恶性肿瘤回声较强、无蒂,活动度小。横纹肌瘤多发生在室壁心肌内,呈结节状,与正常心肌间有明确的界限。结论:ECG对原发心脏肿瘤的诊断具有重要意义,可初步区分良、恶性肿瘤。  相似文献   
56.
Zusammenfassung Im Rahmen einer retrospektiven Untersuchung wurden 50 Resektionen wegen primärer Lebermalignome, die vom 1. 6. 1979 bis zum 31. 12. 1991 an der Chirurgischen Universitätsklinik Köln durchgeführt wurden, analysiert. Die Resektionsrate betrug 28 %. Die Kliniksletalität betrug insgesamt 22 % und konnte in den letzten 5 Jahren auf 4% gesenkt werden. Die Ein-, Dreiund Fünfjahresüberlebensraten betrugen unter Einschluß der Kliniksletalität 55%, 30% und 24%. Wichtigster Prognosefaktor war die chirurgische Radikalität. In einer Literaturanalyse wurden die Ergebnisse von 8725 Leberresektionen wegen primärer Lebermalignome, die zwischen 1980 bis 1992 publiziert wurden, untersucht. Die Resektionsrate betrug im Durchschnitt 32 ± 17%. Die Kliniksletalität konnte von 15 ± 5% (Resektionen vor 1970) auf 6 ± 2% (Resektionen nach 1980) gesenkt werden. Die Ein-, Drei- und Fünfjahresüberlebensraten betrugen 66 ± 17%, 39 ± 15% und 27 ± 10%. Bis auf eine geringere Kliniksletalität asiatischer Studien (4 % vs. 7%) waren die Resektionsraten und Langzeitergebnisse von asiatischen, amerikanischen und europäischen Studien durchaus vergleichbar. Die Langzeitprognose wird in erster Linie durch die erreichte chirurgische Radikalität sowie die Größe und Ausdehnung des Tumors zum Zeitpunkt der Resektion beeinflußt. Die Effektivität adjuvanter Therapien ist noch nicht ausreichend untersucht.
Liver resection for primary liver tumors. Our own results and an analysis of the literature
In a retrospective study we analysed 50 resections for primary liver tumors performed between 1 July 1979 and 31 December 1991 at the Department of Surgery of the University of Cologne. The mean resectability rate was 28 %. Hospital mortality after resection was 22% and could be reduced to 4% during the last 4 years. The overall survival rates after 1, 3 and 5 years were 55%, 30% and 24% respectively. The surgical radicality is the most important prognostic factor. In a review of the literature the results of 8,725 resections for primary liver malignancies published between 1980 and 1992 were analyzed. The mean resectability rate was 32 ± 17%. The hospital mortality after resection could be reduced from 15 ± 5% (resections before 1970) to 6 ± 2 % (resections after 1980). The overall survival rates after 1, 3 and 5 years were 66 ± 17%, 39 ± 15% and 27 ± 10%, respectively. Apart from a lower hospital mortality in Asian studies (4 % vs. 7 %) the resection rates and long-term results of Asian, American and European studies were similar. Long-term prognosis predominantly depended on the surgical radicality and on the size and extension of the tumor at the point of resection. The effectivity of an adjuvant tumor therapy is not analyzed sufficiently.
  相似文献   
57.
本资料对93例不同性质的卵巢肿瘤细胞DNA及RNA含量进行了定量研究,其中50例良性、43例恶性。并对患者进行1~5年的随访。结果是卵巢良性肿瘤的异倍率(假阳性)为44%,恶性肿瘤异倍率为86.0%。以“标准DI”及“标准RI”为指标判断卵巢肿瘤性质的准确率较以“异倍性”为高,且双指标同时应用高于任一单指标:对卵巢良恶性肿瘤的诊断准确率分别为90%和95.3%。提出“标准DI”和“标准RI”是判断卵巢肿瘤性质的理想指标。且DNA及RNA含量与卵巢癌预后有密切关系。  相似文献   
58.
Primary and transplanted ENU induced rat tumors in neurooncology   总被引:1,自引:0,他引:1  
In neurooncology transplanting, tumors can be used for many purposes e.g. to solve questions concerning the etiology and pathogenesis of such tumors or their management. Experimentally induced and transplanted tumors of the nervous system become reproducible in their morphology and growth parameters after about 12 subsequent intracerebral passages. During the period from the first to the 12th intracerebral generations, a simplification of the histology and a reduction of the induction times take place. Nowadays the growth behavior of such tumors can be followed by imaging methods such as MRI if specially adapted to small animals. Our results are based on the investigation of over 2350 experimentally induced tumors of the central and peripheral nervous system that were diagnosed according to the rules of human and rodent brain tumor classification and various subgroups of this sample, analyzed by electron microscopy, postmortal angiography and MRI.  相似文献   
59.
卵巢肿瘤蒂扭转的CT诊断价值探讨(附12例报告)   总被引:2,自引:0,他引:2  
目的:评价CT对卵巢肿瘤蒂扭转的诊断,探讨囊壁局限性增厚对卵巢肿瘤蒂扭转的诊断价值。方法:对12例卵巢肿瘤蒂扭转的CT征象作回顾性分析,对卵巢肿瘤蒂扭转囊壁局限性增厚CT表现与文献报道的B超特征性表现双肿块声像图作对照分析。结果:本组12例病例中11例为卵巢囊性或者囊实性肿瘤,其中6例有局限性囊壁增厚,除此之外卵巢肿瘤蒂扭转还有其它许多CT征象,如卵巢肿瘤囊肿壁及囊肿内出血,附件输卵管增粗、显示,盆腔内积液,子宫位置偏位。结论:只要我们能密切结合临床,CT能对大多数卵巢肿瘤蒂扭转作出正确诊断。  相似文献   
60.
原发性小肠肿瘤诊断治疗的临床分析(附58例报告)   总被引:1,自引:0,他引:1  
目的探讨原发性小肠肿瘤临床特型、病理分型及诊治经验。方法回顾性分析1993年10月。2003年10月收治的有完整资料的58例原发性小肠肿瘤病例。结果本组包括13例(22.4%)良性肿瘤,45例(77.6%)。小肠良性肿瘤均行局部肠段切除,除2例死于其它疾患外,余11例健在;小肠恶性肿瘤患者中,院内死亡6例,仅11例能行根治性肠切除,37例行化疗(总有效率83.4%),随访33例(随访率89.5%),存活5年以上者14例(5年生存率42.4%),多为T细胞性非何杰金淋巴瘤。结论原发性小肠肿瘤恶性所占比例较高,缺乏特征性的临床表现及有效的诊断手段,易致长期延误诊治,预后甚差;对原因不明的腹痛、消化道出血及定位不明的腹部包块患者及早行剖腹探查是避免小肠肿瘤长期误诊、改善患者预后的可靠手段。  相似文献   
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