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91.
Summary Normal oesophagus specimens taken from 65 autopsy cases and surgical specimens from 127 oesophageal carcinoma cases were examined histopathologically to determine melanocyte incidence and distribution. Melanocytes were found in the epithelio-stromal junction in 7.7% of normal oesophagus specimens examined at autopsy, and in 29.9% of surgical cases with oesophageal carcinoma. Positive specimens in the latter groups, especially from pre-operatively irradiated individuals, showed a more remarkable increase of melanocytes than was evident in any of the normal oesophageal samples. There were no significant differences in incidence between males and females, or between age groups. In cases where the cancer invaded into deeper stroma, the melanocytes were mainly observed in the normal epithelium around the carcinomas. Epithelial and stromal elements of the melanotic mucosa commonly showed hyperplastic changes such as acanthosis or basal cell hyperplasia, and chronic oesophagitis. Melanocytes were observed most commonly in the lower part of the oesophagus, the site where malignant melanoma of the oesophagus, most often originates. These results strongly suggest that the melanocyte increase observed in areas of hyperplastic epithelium and chronic oesophagitis may play an important role as a precursor lesion for malignant melanoma in the oesophagus.  相似文献   
92.
目的观察Ⅳ型胶原酶和基底膜在大肠癌生长中的相互关系及Ⅳ型胶原酶的表达与p21的表达之间的关系。方法应用免疫组化双标记方法,对86例人大肠癌组织的Ⅳ型胶原酶表达及基底膜的改变作对照研究。结果大肠癌组织中Ⅳ型胶原酶的阳性率为83.72%(73/86),与对照组癌周正常肠粘膜的阳性率10%差异有非常显著意义(P<0.01)。同时,双染色显示Ⅳ型胶原酶阳性的癌组织基底膜表现为不连续,出现缺口、片段缺失或完全消失等形态。此外,肠癌中Ⅳ型胶原酶的分布与p21的表达呈正相关(r=0.974,p<0.01)。结论Ⅳ型胶原酶的分泌对肠癌基底膜破坏起重要作用,可以作为判断大肠癌生长特性的辅助指标。  相似文献   
93.
我们应用三维结构(3-D)再构成计算机系统,以0.2mm间隔连续切片,HE染色,对50例经纤维结肠镜切除的大肠腺瘤各种异型上皮的体积及分布规律进行研究。其中癌变17例(34%),其平均体积是单纯腺瘤的3.4倍。腺瘤体积越大,其癌变率越高,但体积较小的亚有蒂型腺瘤也有很高癌变率(25%)。研究结果表明腺瘤体积大小与平均异型度无相关关系。用常规方法切片,仅检出14例有癌变,漏诊率18%。为提高腺瘤癌变检出率,至少应以0.6mm间隔连续切片。此种方法对准确判定断端有无癌浸润也有重要意义。  相似文献   
94.
肢端黏液样炎性纤维母细胞肉瘤2例及文献复习   总被引:1,自引:2,他引:1  
目的探讨肢端黏液样炎性纤维母细胞肉瘤的临床病理学特征及鉴别诊断。方法对2例发生在下肢末端的黏液样炎性纤维母细胞肉瘤进行光镜观察和免疫组化标记,并复习文献。结果2例发生在下肢末端的病程较长的渐进性肿块,术后局部复发。镜检:病变呈多结节状,边界不清;黏液样基质中见数量不等的各类炎细胞浸润,散在或灶性分布梭形、奇异形和多空泡状脂肪母细胞样3种形态的瘤细胞。免疫表型:肿瘤细胞Vim弥漫阳性,CD68和CD34灶性阳性,CK、SMA、HHF-35、S-100蛋白、CD45、CD45R0、CD15、CD30均阴性。结论此病病程较长,术后易局部复发,是一种低度恶性的肿瘤。鉴于病变黏液样基质及各类炎细胞浸润的背景较为突出,而特征性的瘤细胞稀疏,应注意与炎症性病变或具有相似组织形态的良性或恶性肿瘤鉴别。  相似文献   
95.
A case of nasopharyngeal carcinoma is presented. Epstein-Barr viral genome was identified in the neoplastic cells by in situ hybridization with digoxigeninlabelled polymerase chain reaction-generated probes. We report the development of this technique in paraffinembedded sections and propose that such identification may prove valuable for the diagnosis of this tumour in routine material.P. Delvenne is a research associate of the National Fund for Scientific Research (Belgium)  相似文献   
96.
Web-based virtual microscopy in teaching and standardizing Gleason grading   总被引:6,自引:0,他引:6  
Gleason grading forms the basis of prognostic and therapeutic assessment in prostatic carcinoma despite its subjective nature and substantial interobserver variation. The accuracy of Gleason grading can be improved by the use of educational tools such as reference images. However, conventional microscopy images are of limited educational value because it is neither possible to view the sample at different magnifications nor to navigate into different areas of the specimen. This limitation can be overcome by the use of virtual microscopy, which allows viewing entire digitized microscope slides. We created an interactive Web site ( www.webmicroscope.net/gleason ) featuring a comprehensive set of prostatic needle biopsies as virtual slides, which can be viewed with a standard Web browser (Internet Explorer or Netscape). To evaluate the validity of Web-based virtual microscopy for Gleason grading, an experienced uropathologist (TK) scored a series of 62 biopsies from the original glass slides and 6 weeks later from virtual slides on the Web site using an ordinary desktop computer. The intraobserver agreement was excellent, with identical Gleason scores found in 48 of the 62 cases ( kappa = 0.73). The 14 remaining scores differed only by 1 point on the Gleason scale (2-10). The virtual slides were viewed by 2 other uropathologists (PM and HH), with interobserver kappa coefficients ranging from 0.55 to 0.62, which is within the range of previously reported studies using glass slides. The 3 uropathologists' Gleason scores were included as reference scores on the Web site, which now serves as a publicly open platform for self-testing and learning of Gleason grading. We conclude that Web-based virtual microscopy is a promising new tool for teaching and standardizing Gleason grading.  相似文献   
97.
Although infantile myofibromatosis (IM) is the most common fibrous proliferation of infancy, many aspects of this benign lesion have not been explored. IM histogenesis is still poorly understood, despite immunohistochemical staining and ultrastructural features that suggest a myofibroblastic origin. IM diagnosis is often made difficult by the predominance of small primitive spindle cells over myofibrobasts and the presence of intravascular growth. Genetic information is scarce, with only one karyotyped case. Here we describe a case of solitary IM discovered at birth in an otherwise healthy girl. The tumor was well circumscribed, arranged in nodules and made up of ovoid cells without atypia, in a myxoid background. Immunohistochemical evaluation indicated a myofibroblastic differentiation. The cytogenetic and fluorescence in situ hybridization analyses revealed an abnormal chromosome 9, derived from an unbalanced whole-arm translocation between chromosomes 9 and 16. On both chromosomes, the breakpoints were located in the pericentric heterochromatic region. This clonal abnormality has not been reported in other tumors and is different from the chromosome 6q deletion reported in the single previous reported IM karyotype.  相似文献   
98.
Summary Seventy-five livers with metastases were cut sagitally into 1 cm thick slices. A total number of 11,581 metastases sections was exactly mapped. There was an average of 154 metastases sections per liver. The average diameter of the metastases was 1 cm. 40% of the metastases reached to the hepatic surface, and 60% were invisible due to their deposition in the internal parenchyma. In 8% of the livers there were only superficial metastases (average 3.2 metastases), and in 12% were only deep metastases detected (average 2.6). The total number of superficial metastases increased with increasing diameter of the secondary tumors.An approximately homogeneous distribution of hepatic metastases within the liver parenchyma has been demonstrated.  相似文献   
99.
NF-κB在人肝细胞肝癌中的表达及与HBV X蛋白的关系   总被引:2,自引:0,他引:2  
目的:研究核转录因子NF--κB在人肝细胞肝癌组织中的表达及其与乙型肝炎病毒(HBV )X蛋白的关系。方法;用免疫组织化学S-P法,检测52例人肝细胞肝癌组织中核转录因子NF--κB及HBV X蛋白的表达;用脂质体介导的基因转染法将HBV x基因真核表达载体pcDNA3.1-HBX转染入人肝癌细胞系HCC-9204,检测肝癌细胞内核转录因子NF--κB的表达。结果:52例人肝细胞肝癌组织均有核转录因子NF--κB的广泛表达,并且在11例HBV X蛋白阳性的肝癌组织,核转录因子NF--κB位于细胞胞质和胞核,而在41例HBV X蛋白阴性的肝癌组织,核转录因子NF--κB位于肝癌细胞的胞质。将HBV x基因真核表达载体pcDNA3.1-HBX转染 入人肝癌细胞系HCC-9204,并在稳定表达X蛋白 的肝癌细胞,核转录因子NF--κB定位于其胞质和胞核,而未进行基因转染的亲体细胞,核转录因子NF--κB仅定位于细胞质,细胞核无核转录因子NF--κB的表达。结论:核转录因子NF--κB在人肝细胞肝癌组织中广泛表达,人肝细胞肝癌中存在着核转录因子NF--κB的异常激活,并且核转录因子NF--κB的异常激活与HBV X蛋白有关,X蛋白激活核转录因子NF--κB, 使其从细胞转位于细胞核,这可能在HBV相关的人原发性肝癌肝癌的发生中起一定作用。  相似文献   
100.
Nonulcerative penile mass lesions are rare. Pathological diagnosis of these lesions would traditionally be a biopsy. We report two such primary penile lesions which were diagnosed by fine-needle aspiration cytology (FNAC). Both lesions were present in the shaft and were diagnosed as squamous cell carcinoma (SCC). The first patient had a recurrence on the penile stump of partial amputation without any ulceration. The second had a primary urethral carcinoma on the terminal penile shaft infiltrating the corpora cavernosa dorsally. Open biopsies were avoided in both cases. FNAC was associated with very little and tolerable discomfort. There were no complications. The aspirate yield was sufficient for cytological diagnosis. FNAC of nonulcerated penile lesions is safe, well tolerated, and capable of providing a cytological diagnosis. Hence, it is a very useful outpatient procedure and could be the procedure of choice for diagnosis.  相似文献   
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