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991.
Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post-transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non-mucinous bronchioloalveolar carcinoma in a 43-year-old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty-five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non-mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease.  相似文献   
992.
993.
Lung carcinoma with sarcomatous transformation (LCST) is highly aggressive and characterized by local invasion and/or distant metastasis, which leads to a shorter survival than ordinary lung carcinomas. Therefore, to elucidate whether the malignant potential of the spindle cell element in LCST is associated with the alteration of the p53 gene, four cases were examined by analyses of overexpression of the p53 oncoprotein, mutation of the p53 gene and loss-of-heterozygosity (LOH) at chromosome 17p. In two cases overexpression of the p53 oncoprotein of the spindle cell component showed a higher degree of staining than that of the carcinoma component; LOH was identified in both carcinoma and sarcomatous components in one case, while in contrast, another case showed LOH in the sarcomatous component only. Mutations were clearly detected in two cases; one showed a CTT to CGT transversion in codon 194 of exon 6 in both components, whereas the other showed a CTG to CAG transversion in codon 265 of exon 8 in the sarcomatous component only. On the basis of these observations, it suggested that the sarcomatous component shows a higher frequency of p53 gene abnormalities in comparison to the carcinoma component. These results also suggested that the acquisition of malignant potential in the sarcomatous component, or the morphological alteration of carcinoma cells, is correlated with abnormalities associated with the p53 gene.  相似文献   
994.
Effects of suramin, a polysulfonated naphthylurea compound, on metastatic ability, proliferation, and production of plasminogen activators and plasminogen activator inhibitors were studied using the highly metastatic human renal cell carcinoma cell line, SN12C-PM6. After renal subscapular implantation of tumor cells in nude mice, suramin significantly inhibited metastasis of tumor cells to the lungs and liver. In vitro growth of tumour cells was inhibited by suramin in a dose-dependent manner, at relatively low doses (ID50 = 105 µg/ml). Plasminogen activator inhibitor type 2 (PAI-2) production by tumor cells was enhanced by suramin (100 µg/ml), whereas urokinase-type plasminogen activator (uPA) production was suppressed. Thus, the increase in PAI-2 and the decrease in uPA production correlated with the inhibitory effects on tumour growth and metastasis by suramin. Therefore suramin may be beneficial for the treatment of patients with an early stage of renal cancer with potential risk of metastasis.  相似文献   
995.
生物学行为是影响胃癌预后的重要因素而核面积是影响因素中最重要一个。本文按生长方式对胃癌作了新的病理生物学分型的尝试,把胃癌分作膨胀型和浸润型,每型又依核面积大小分为大核型和小核型。结果表明,本文的分型较其他分型更能体现肿瘤的生物学特性,值得提倡。  相似文献   
996.
Cytokines released from tumour cells may have function as signals to neighbouring immune and inflammatory cells. Several studies have shown that the immunoregulatory cytokines IL-10 and transforming growth factor-beta 1 (TGF-β1) as well as prostaglandin-E2 (PGE2) play an important role in tumour-induced immunosuppression. The aim of the study was to investigate the effect of colon carcinoma cell lines on IL-10 production in peripheral monocytes (PBMC) and lamina propria mononuclear cells (LPMC). We examined four colon carcinoma cell lines (HT-29, Caco-2, Colo-320 and HCT-116) and determined their production of TGF-β1, IL-10 and PGE2. Peripheral monocytes were isolated by density gradient centrifugation and LPMC were isolated from surgical specimens using a collagenase digestion method. Monocytes and LPMC were cultured with colon carcinoma cell conditioned medium or in co-culture with colon carcinoma cells. Supernatants were then determined for the production of IL-10 by ELISA assays. All colon carcinoma cell lines stimulated peripheral monocytes as well as LPMC to produce markedly increased levels of IL-10. Colon cancer cells secreted negligible levels of IL-10, but high amounts of TGF-β1 and PGE2. Neutralization of TGF-β1 by administration of anti-TGF-β as well as neutralization of PGE2 with anti-PGE2 antisera reduced the IL-10 production of monocytes markedly, indicating that tumour cell-derived TGF-β1 and PGE2 are major factors for IL-10 stimulation. In vitro stimulation of monocytes with TGF-β1 and PGE2 could confirm that TGF-β1 as well as PGF2 at picogram concentrations were able to prime monocytes for enhanced IL-10 production. Our results demonstrate that colon carcinoma cell lines enhance the ability of monocytes and intestinal macrophages to produce IL-10. The stimulation of monocyte IL-10 by colon cancer cell-derived TGF-β1 and PGE2 may act as a tumour-protecting mechanism by impairing the activation of anti-tumour cytokines.  相似文献   
997.
A 57-year-old woman presented with a 10×10 cm anterior mediations mass. The tumor had Invaded the pericardium, both lungs and the left brachiocephallc vein, and was treated by partial resection and postoperative radiation therapy. Pathological examination of the tumor revealed squamous cell carcinoma with a spindle cell sarcomatous component. Immunohistochemically, keratin and epithelial membrane antlgen were posltive In both the spindle cell sarcomatous areas and the squamous cell carcinomatous area and thus, a diagnosis of thymic carcinoma of sarcomatoid type was made. The patient died of recurrent disease 1 year after surgery. This case is the seventh reported In the English literature Because of the poor outcome, adjuvant therapy is recommended.  相似文献   
998.
对30例膨胀型肝癌和20例浸润型肝癌作病理组织学分析,并对20例膨胀型和浸润型肝癌进行超微结构和免疫组化研究。结果显示,膨胀型肝癌的生物学特性和浸润型肝癌显著不同。膨胀型肝癌癌组织分化较好、侵袭性较小、增殖程度较低、癌巢周围基膜发育良好、瘤结节周围均有包膜而呈膨胀性生长,但包膜内浸润的微癌灶十分常见,多达70%。提示此型有潜在的较强侵袭性和向浸润型肝癌转化的倾向。  相似文献   
999.
The newly discovered molecular features of well-differentiated thyroid carcinomas derived from follicular cells are reviewed, within the frame of the 2004 WHO classification of thyroid tumours, under the following headings: “Follicular carcinoma”, “Papillary carcinoma”, “Follicular variant of papillary carcinoma” and “Hürthle cell tumours”. A particular emphasis is put on the meaning of PAX8–PPARγ rearrangements, RAS and BRAF mutations, and deletions and mutations of mitochondrial genes and of nuclear genes encoding for mitochondrial enzymes, for thyroid tumorigenesis.  相似文献   
1000.
乳腺富糖原透明细胞癌2例报道及文献复习   总被引:1,自引:1,他引:1  
目的 探讨乳腺富糖原透明细胞癌临床病理特点及鉴别诊断要点。方法 对2例乳腺富糖原透明细胞癌进行临床资料及光镜和免疫组化标记观察。结果 组织学特点:癌细胞为多边形或柱状,胞界清楚,胞质透明,呈实性巢状、片状排列,可有乳头形成。表现为导管内癌和浸润性癌结构。免疫组化染色显示:癌细胞呈上皮性免疫表型,CK(AE1)、CEA强阳性,不表达S-100蛋白、肌动蛋白。PAS染色阳性。结论 富含糖原透明细胞癌是上皮性特殊类型乳腺癌,其诊断主要依靠组织病理学和免疫组化标记。  相似文献   
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