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991.
Yolk sac tumor in a young girl: a case report.   总被引:1,自引:0,他引:1  
BACKGROUND: Yolk sac tumor is a rare neoplasm characterized by high malignancy given its premature metastasis, that is frequent in adolescence. CASE REPORT: A 21-year-old woman came to our observation for an ovarian cyst (13 cm in diameter). Following salpingo-oophorectomy, it was revealed as a yolk sac tumor by histological diagnosis. The patient exhibited a highly elevated level of alpha1-fetoprotein (AFP) (1156 UI/ml). She is now undergoing chemotherapy treatment. CONCLUSION: This is an interesting case of yolk sac tumor in a young girl, at an age typical for germ cell tumor. AFP represents a valid marker resulting in a useful diagnostic tool.  相似文献   
992.
De Stefano  N.  Narayanan  S.  Mortilla  M.  Guidi  L.  Bartolozzi  M.L.  Federico  A.  Arnold  D.L. 《Neurological sciences》2000,21(2):S883-S887
Axonal damage in multiple sclerosis has become an important issue. This has been emphasized by recent in vivo proton magnetic resonance (MR) spectroscopy and in vitro pathology studies that have found axonal damage in both lesions and the surrounding normal-appearing white matter. In particular, proton MR spectroscopy, by monitoring levels of N-acetylaspartate (a putative marker of axonal integrity), has been particularly illuminating, as the extent of axonal injury associated with white matter inflammation and demyelination had not been well appreciated from classical pathology studies. Recent MR data demonstrate that cerebral axonal damage begins and contributes to disability from the earliest stages of the disease. This implies that the apparently primary role of axonal damage and loss in the pathogenesis of the disease should be given due importance, and argues for the early treatment of multiple sclerosis with agents directed not only against inflammation, but also towards axonal protection.  相似文献   
993.
背景:目前认为,心肌梗死(myocardial infarction,MI)和缺血性卒中与金属蛋白酶(metallopmteinases,MMPs)消化基质,导致动脉粥样斑块破裂有关。环氧合酶2(COX-2)和前列腺素E2合成可诱导巨噬细胞MMPs和MMP-9的产生。尽管COX-2的表达由遗传决定,但是COX-2多态性与MI和卒中发病危险的关系仍不清楚。  相似文献   
994.
PURPOSE: The aim of this study was to acquire further insights into the pathogenetic pathways of head and neck squamous cell carcinomas (HNSCC) that may be useful for identifying new biomarkers instrumental in developing more specific treatment approaches. EXPERIMENTAL DESIGN: Cell cycle regulators and epidermal growth factor receptor (EGFR) and BRAF genes were analyzed in a series of 90 oropharyngeal SCCs of a cohort of surgically treated patients from a single institution, and the results were matched with the presence of high-risk human papillomavirus (HR-HPV) DNA and the TP53 status. RESULTS: At least four distinct groups of tumors were identified sharing a common histology but displaying different molecular/cytogenetic patterns: (a) 19% were HPV-positive SCCs whose lack of alterations of the investigated genes could explain their particular natural history, which requires less aggressive treatment; (b) 37% were HPV-negative SCCs carrying TP53 mutations, which may be more effectively treated by drugs acting through p53-independent apoptosis; (c) 34% were HPV-negative SCCs carrying wild-type TP53 and loss of 9p21 (p16INK4a and p15INK4b) and/or cyclin D1 overexpression that justify treatment with DNA-damaging drugs followed by cell cycle inhibitors; and (d) 10% were HPV-negative lacking tumor suppressor genes and cell cycle alterations. The second, third, and fourth groups also showed an increased copy number of EGFR and chromosome 7 (43%) that might justify the additional or alternative use of EGFR inhibitors. CONCLUSIONS: Our findings suggest that assessing HPV, TP53, 9p21, and EGFR status may be crucial to finding more tailored and beneficial treatments for oropharyngeal SCCs.  相似文献   
995.
PURPOSE: We sought to demonstrate that a single systemic administration of L19mTNFalpha (a fusion protein constituted by the scFv L19 specific for the oncofetal ED-B domain of fibronectin and tumor necrosis factor alpha, TNFalpha) in combination with melphalan induced complete and long-lasting tumor eradication in tumor-bearing mice and triggered the generation of a specific T cell-based immune response that protects the animals from a second tumor challenge, as well as from challenges with syngeneic tumor cells of different histologic origin. Experimental Design and RESULTS: Treatment with L19mTNFalpha, in combination with melphalan, induced complete tumor regression in 83% of BALB/c mice with WEHI-164 fibrosarcoma and 33% of animals with C51 colon carcinoma. All cured mice rejected challenges with the same tumor cells and, in a very high percentage of animals, also rejected challenges with syngeneic tumor cells of different histologic origin. In adoptive immunity transfer experiments, the splenocytes from tumor-cured mice protected naive mice both from C51 colon carcinoma and from WEHI-164 fibrosarcoma. Similar results were also obtained in adoptive immunity transfer experiments using severely immunodepressed mice. Experiments using depleted splenocytes showed that T cells play a major role in tumor rejection. CONCLUSIONS: The results show that the selective targeting of mTNFalpha to the tumor enhances its immunostimulatory properties to the point of generating a therapeutic immune response against different histologically unrelated syngeneic tumors. These findings predicate treatment approaches for cancer patients based on the targeted delivery of TNFalpha to the tumor vasculature.  相似文献   
996.
997.
PURPOSE: To assess the value of changes in the expression of topoisomerase IIalpha (TopoII) and the proto-oncogene erbB-2 (HER-2) as predictors of relapse-free survival in women with operable breast cancer treated with anthracycline-based neoadjuvant chemotherapy. PATIENTS AND METHODS: Seventy-seven patients with primary breast cancer who had undergone neoadjuvant anthracycline-based chemotherapy were included in the present study. TopoII and HER-2 were measured by immunohistochemistry in prechemotherapy and postchemotherapy (at the time of surgery) tumor specimens, and the value of their changes as predictors of relapse-free survival were evaluated by Kaplan-Meier and Cox proportional hazard regression analyses. RESULTS: Neoadjuvant chemotherapy resulted in a significant reduction in the percentage of cells expressing TopoII (P < 0.0001). No significant change was observed for HER-2. TopoII and HER-2 expression before chemotherapy predicted tumor response to treatment. Changes in TopoII expression after chemotherapy were strongly associated with a poor relapse-free survival (P < 0.0001) in a Cox multivariate analysis adjusted for other clinicopathologic prognostic factors. CONCLUSION: Changes in TopoII expression after anthracycline-based neoadjuvant chemotherapy is an independent predictor of a poor relapse-free survival in patients with breast cancer. Tumor cells displaying an increased TopoII expression after treatment may be responsible for relapses, and may, therefore, define a group of patients with anthracycline-resistant breast cancer.  相似文献   
998.
From March 1996 to December 1999 we performed 1,266 sentinel node biopsies (SNBs) in patients with small breast cancers. The technique is to inject technetium 99m-labeled albumin particles close to the tumor, locate the sentinel node (SN) scintigraphically, and use a handheld gamma-detecting probe to guide its removal via a small incision during breast surgery. Our experience was divided into three phases. In the first phase, complete axillary dissection was performed to assess the accuracy of SNB in predicting axillary status. We also assessed safety, perfected tracer injection technique, determined optimal particle size and radioactivity levels, optimized lymphoscintigraphic scanning, and perfected the surgical technique. The SN was identified and removed in 98.7% of cases. Comparison with complete axillary dissection showed that the SN predicted axillary status in 96.8% of cases. However, use of an intraoperative frozen section method predicted axillary status in only 86.5% of cases. In the second phase we developed a new method for intraoperative histologic analysis. Extensive sampling (up to 60 sections/SN) and an experienced pathologist proved more important than use of antikeratin immunostaining in identifying tumor cells, and the new method has the accuracy of a definitive histologic examination. The third phase, a randomized trial, closed at the end of 1999. Trial objectives were to confirm that the SN predicts axillary status, to determine the number of axillary relapses, and to assess overall and disease-free survival. Patients were randomized in the operating room to complete axillary dissection or SNB. If the SN was positive, complete axillary dissection was performed; if the SN was negative, no further axillary treatment was given. We expect the trial to confirm our clinical experience that SNB is a safe and accurate procedure for staging patients with early breast cancer and a clinically negative axilla.  相似文献   
999.
PURPOSE: To appraise the performance of Comprehensive Geriatric Assessment (CGA) in elderly cancer patients (> or = 65 years) and to evaluate whether it could add further information with respect to the Eastern Cooperative Oncology Group performance status (PS). PATIENTS AND METHODS: We studied 363 elderly cancer patients (195 males, 168 females; median age, 72 years) with solid (n = 271) or hematologic (n = 92) tumors. In addition to PS, their physical function was assessed by means of the activity of daily living (ADL) and instrumental activities of daily living (IADL) scales. Comorbidities were categorized according to Satariano's index. The association between PS, comorbidity, and the items of the CGA was assessed by means of logistic regression analysis. RESULTS: These 363 elderly cancer patients had a good functional and mental status: 74% had a good PS (ie, lower than 2), 86% were ADL-independent, and 52% were IADL-independent. Forty-one percent of patients had one or more comorbid conditions. Of the patients with a good PS, 13.0% had two or more comorbidities; 9.3% and 37.7% had ADL or IADL limitations, respectively. By multivariate analysis, elderly cancer patients who were ADL-dependent or IADL-dependent had a nearly two-fold higher probability of having an elevated Satariano's index than independent patients. A strong association emerged between PS and CGA, with a nearly five-fold increased probability of having a poor PS (ie, > or = 2) recorded in patients dependent for ADL or IADL. CONCLUSION: The CGA adds substantial information on the functional assessment of elderly cancer patients, including patients with a good PS. The role of PS as unique marker of functional status needs to be reappraised among elderly cancer patients.  相似文献   
1000.
The pivotal role of vascular endothelial growth factor (VEGF-A) in the regulation of angiogenesis, in particular in the onset and maintenance of tumor angiogenesis, has been demonstrated repeatedly in experimental model systems and, more recently, in clinical trials. Experimental evidence has also suggested that up-regulated expression of VEGF-A may cooperate with other genetic or epigenetic changes to induce or accelerate tumor progression to invasive and metastatic cancers. Here we report the generation of transgenic mouse lines that express human VEGF-A165 under the control of the rat insulin promoter in the beta cells of pancreatic islets of Langerhans (Rip1VEGF-A). These mice do not exhibit detectable changes in islet development, vascularization, or physiology. Intercrosses of these mice with a transgenic mouse model of pancreatic beta cell carcinogenesis (Rip1Tag2) result in an earlier onset of tumor angiogenesis and with it accelerated tumor growth and mortality. The transition from benign tumors (adenoma) to malignant tumors (carcinoma) is modestly accelerated; however, tumor metastases are not observed. Our findings indicate that in beta-cell tumorigenesis, overexpression of VEGF-A165 accelerates the onset of tumor angiogenesis and with it tumor progression but is not sufficient to induce tumor metastasis.  相似文献   
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