939 resultados para tumor margins


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OBJECT: Ultrasound may be a reliable but simpler alternative to intraoperative MR imaging (iMR imaging) for tumor resection control. However, its reliability in the detection of tumor remnants has not been definitely proven. The aim of the study was to compare high-field iMR imaging (1.5 T) and high-resolution 2D ultrasound in terms of tumor resection control. METHODS: A prospective comparative study of 26 consecutive patients was performed. The following parameters were compared: the existence of tumor remnants after presumed radical removal and the quality of the images. Tumor remnants were categorized as: detectable with both imaging modalities or visible only with 1 modality. RESULTS: Tumor remnants were detected in 21 cases (80.8%) with iMR imaging. All large remnants were demonstrated with both modalities, and their image quality was good. Two-dimensional ultrasound was not as effective in detecting remnants<1 cm. Two remnants detected with iMR imaging were missed by ultrasound. In 2 cases suspicious signals visible only on ultrasound images were misinterpreted as remnants but turned out to be a blood clot and peritumoral parenchyma. The average time for acquisition of an ultrasound image was 2 minutes, whereas that for an iMR image was approximately 10 minutes. Neither modality resulted in any procedure-related complications or morbidity. CONCLUSIONS: Intraoperative MR imaging is more precise in detecting small tumor remnants than 2D ultrasound. Nevertheless, the latter may be used as a less expensive and less time-consuming alternative that provides almost real-time feedback information. Its accuracy is highest in case of more confined, deeply located remnants. In cases of more superficially located remnants, its role is more limited.

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Tumor necrosis factor (TNF) is cleaved proteolytically from a 26-kilodalton transmembrane precursor protein into secreted 17-kilodalton monomers. Transmembrane (tm) and secreted trimeric TNF are biologically active and may mediate distinct activities. We assessed the consequences of a complete inhibition of TNF processing on the course of colitis in recombination activating gene (RAG)2 -/- mice on transfer of CD4 CD45RB hi T cells.

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A great share of literature on social exclusion has been based mainly on the analysis of official survey data. Whereas these efforts have provided insights into the characteristics and conditions of those people living at the margins of mainstream social relations, they have however failed to encompass those who live beyond these very margins. Meanwhile, research on these hidden subpopulations, such as homeless and other vulnerable groups, remains generally less abundant and is significantly detached from the theoretical core of the debate on social exclusion. The concern about these shortcomings lies at the heart of our research. We seek to bring some light to the area by using data made available by an organization that provides services to people experiencing homelessness in Barcelona (Spain). The data sample contains clients in early stages of exclusion and others in chronic situations. Thus, we attempt to identify some of the variables that operate in preventing the "chronification" of those individuals in situation of social exclusion. Our findings suggest that certain variables such as educational level, income and housing type, which are considered to be central predictors in the analysis of poverty, behave differently when analyzing differences between stages of social exclusion. Although these results cannot be extrapolated to the whole Spanish or European reality, they could provide useful insight for future investigations on this topic.

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The extracellular matrix molecule tenascin-C (TNC) is a major component of the cancer-specific matrix, and high TNC expression is linked to poor prognosis in several cancers. To provide a comprehensive understanding of TNC's functions in cancer, we established an immune-competent transgenic mouse model of pancreatic β-cell carcinogenesis with varying levels of TNC expression and compared stochastic neuroendocrine tumor formation in abundance or absence of TNC. We show that TNC promotes tumor cell survival, the angiogenic switch, more and leaky vessels, carcinoma progression, and lung micrometastasis. TNC downregulates Dickkopf-1 (DKK1) promoter activity through the blocking of actin stress fiber formation, activates Wnt signaling, and induces Wnt target genes in tumor and endothelial cells. Our results implicate DKK1 downregulation as an important mechanism underlying TNC-enhanced tumor progression through the provision of a proangiogenic tumor microenvironment.

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The present study reports on the surgical and prosthodontic rehabilitation of 46 patients, 31 male and 15 female, after resection of oral tumors. The treatment was carried out from 2004 to 2007 at the Department of Prosthodontics, University of Bern, with a follow-up time of 3 to 6 years. The average age at diagnosis was 54 years. 76% of all tumors were squamous cell carcinoma, followed by adenocarcinoma. Resection of the tumors including soft and/or hard tissues was performed in all patients. 80% of them additionally underwent radiotherapy and 40% chemotherapy. A full block resection of the mandible was perfomed in 23 patients, and in 10 patients, the tumor resection resulted in an oronasal communication. 29 patients underwent grafting procedures, mostly consisting of a free fibula flap transplant. To enhance the prosthetic treatment outcome and improve the prosthesis stability, a total of 114 implants were placed. However, 14 implants were not loaded because they failed during the healing period or the patient could not complete the final treatment with the prostheses. The survival rate of the implants reached 84.2% after 4 to 5 years. Many patients were only partially dentate before the tumors were detected, and further teeth had to be extracted in the course of the tumor therapy. Altogether, 31 jaws became or remained edentulous. Implants provide stability and may facilitate the adaptation to the denture, but their survival rate was compromised. Mostly, patients were fitted with removable prostheses with obturators in the maxilla and implant-supported complete dentures with bars in the mandible. Although sequelae of tumor resection are similar in many patients, the individual intermaxillary relations, facial morphology and functional capacity vary significantly. Thus, individual management is required for prosthetic rehabilitation.

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Melanoma is the most common oral tumor in dogs, characterized by rapid growth, local invasion, and high metastatic rate. The goal of this study was to evaluate the combination of radiation therapy and DNA tumor vaccine. We hypothesized, that the concurrent use would not increase toxicity. Nine dogs with oral melanoma were treated with 4 fractions of 8 Gray at 7-day intervals. The vaccine was given 4 times every 14 days, beginning at the first radiation fraction. Local acute radiation toxicities were assessed according to the VRTOG toxicity scoring scheme over a time period of 7 weeks. In none of the evaluated dogs, mucositis, dermatitis and conjunctivitis exceeded grade 2. In 3 dogs mild fever, lethargy, and local swelling at the injection site were seen after vaccine application. In conclusion, the concurrent administration of radiation therapy and vaccine was well tolerated in all dogs.

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BACKGROUND Complete resection of enhancing tumor as assessed by early (<72 hours) postoperative MRI is regarded as the optimal result in glioblastoma surgery. As yet, there is no consensus on standard procedure if post-operative imaging reveals unintended tumor remnants. OBJECTIVE The current study evaluated the feasibility and safety of an early re-do surgery aimed at completing resections with the aid of 5-ALA fluorescence and neuronavigation after detection of enhancing tumor remnants on post-operative MRI. METHODS From October 2008 to October 2012 a single center institutional protocol offered a second surgery within one week to patients with unintentional incomplete glioblastoma resection. We report on the feasibility of the use 5-ALA fluorescence guidance, the extent of resection (EOR) rates and complications of early re-do surgery. RESULTS Nine of 151 patients (6%) with glioblastoma resections had an unintentional tumor remnant with a volume >0.175 cm(3). 5-ALA guided re-do surgery completed the resection (CRET) in all patients without causing neurological deficits, infections or other complications. Patients who underwent a re-do surgery remained hospitalized between surgeries, resulting in a mean length of hospital stay of 11 days (range 7-15), compared to 9 days for single surgery (range 3-23; p=0.147). CONCLUSION Our early re-do protocol led to complete resection of all enhancing tumor in all cases without any new neurological deficits and thus provides a similar oncological result as intraoperative MRI (iMRI). The repeated use of 5-ALA induced fluorescence, used for identification of small remnants, remains highly sensitive and specific in the setting of re-do surgery. Early re-do surgery is a feasible and safe strategy to complete unintended subtotal resections.

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Background Tissue microarray (TMA) technology revolutionized the investigation of potential biomarkers from paraffin-embedded tissues. However, conventional TMA construction is laborious, time-consuming and imprecise. Next-generation tissue microarrays (ngTMA) combine histological expertise with digital pathology and automated tissue microarraying. The aim of this study was to test the feasibility of ngTMA for the investigation of biomarkers within the tumor microenvironment (tumor center and invasion front) of six tumor types, using CD3, CD8 and CD45RO as an example. Methods Ten cases each of malignant melanoma, lung, breast, gastric, prostate and colorectal cancers were reviewed. The most representative H&E slide was scanned and uploaded onto a digital slide management platform. Slides were viewed and seven TMA annotations of 1 mm in diameter were placed directly onto the digital slide. Different colors were used to identify the exact regions in normal tissue (n = 1), tumor center (n = 2), tumor front (n = 2), and tumor microenvironment at invasion front (n = 2) for subsequent punching. Donor blocks were loaded into an automated tissue microarrayer. Images of the donor block were superimposed with annotated digital slides. Exact annotated regions were punched out of each donor block and transferred into a TMA block. 420 tissue cores created two ngTMA blocks. H&E staining and immunohistochemistry for CD3, CD8 and CD45RO were performed. Results All 60 slides were scanned automatically (total time < 10 hours), uploaded and viewed. Annotation time was 1 hour. The 60 donor blocks were loaded into the tissue microarrayer, simultaneously. Alignment of donor block images and digital slides was possible in less than 2 minutes/case. Automated punching of tissue cores and transfer took 12 seconds/core. Total ngTMA construction time was 1.4 hours. Stains for H&E and CD3, CD8 and CD45RO highlighted the precision with which ngTMA could capture regions of tumor-stroma interaction of each cancer and the T-lymphocytic immune reaction within the tumor microenvironment. Conclusion Based on a manual selection criteria, ngTMA is able to precisely capture histological zones or cell types of interest in a precise and accurate way, aiding the pathological study of the tumor microenvironment. This approach would be advantageous for visualizing proteins, DNA, mRNA and microRNAs in specific cell types using in situ hybridization techniques.

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Multimodal therapy concepts have been successfully implemented in the treatment of locally advanced gastrointestinal malignancies. The effects of neoadjuvant chemo- or radiochemotherapy such as scarry fibrosis or resorptive changes and inflammation can be determined by histopathological investigation of the subsequent resection specimen. Tumor regression grading (TRG) systems which aim to categorize the amount of regressive changes after cytotoxic treatment mostly refer onto the amount of therapy induced fibrosis in relation to residual tumor or the estimated percentage of residual tumor in relation to the previous tumor site. Commonly used TRGs for upper gastrointestinal carcinomas are the Mandard grading and the Becker grading system, e.g., and for rectal cancer the Dworak or the Rödel grading system, or other systems which follow similar definitions. Namely for gastro-esophageal carcinomas these TRGs provide important prognostic information since complete or subtotal tumor regression has shown to be associated with better patient's outcome. The prognostic value of TRG may even exceed those of currently used staging systems (e.g., TNM staging) for tumors treated by neoadjuvant therapy. There have been some limitations described regarding interobserver variability especially in borderline cases, which may be improved by standardization of work up of resection specimen and better training of histopathologic determination of regressive changes. It is highly recommended that TRG should be implemented in every histopathological report of neoadjuvant treated gastrointestinal carcinomas. The aim of this review is to disclose the relevance of histomorphological TRG to accomplish an optimal therapy for patients with gastrointestinal carcinomas.

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Histopathologic tumor regression grades (TRGs) after neoadjuvant chemotherapy predict survival in different cancers. In bladder cancer, corresponding studies have not been conducted. Fifty-six patients with advanced invasive urothelial bladder cancer received neoadjuvant chemotherapy before cystectomy and lymphadenectomy. TRGs were defined as follows: TRG1: complete tumor regression; TRG2: >50% tumor regression; TRG3: 50% or less tumor regression. Separate TRGs were assigned for primary tumors and corresponding lymph nodes. The prognostic impact of these 2 TRGs, the highest (dominant) TRG per patient, and competing tumor features reflecting tumor regression (ypT/ypN stage, maximum diameter of the residual tumor) were determined. Tumor characteristics in initial transurethral resection of the bladder specimens were tested for response prediction. The frequency of TRGs 1, 2, and 3 in the primary tumors were n=16, n=19, and n=21; corresponding data from the lymph nodes were n=31, n=9, and n=16. Interobserver agreement in determination of the TRG was strong (κ=0.8). Univariately, all evaluated parameters were significantly (P≤0.001) related to overall survival; however, the segregation of the Kaplan-Meier curves was best for the dominant TRG. In multivariate analysis, only dominant TRG predicted overall survival independently (P=0.035). In transurethral resection specimens of the chemotherapy-naive bladder cancer, the only tumor feature with significant (P<0.03) predictive value for therapy response was a high proliferation rate. In conclusion, among all parameters reflecting tumor regression, the dominant TRG was the only independent risk factor. A favorable chemotherapy response is associated with a high proliferation rate in the initial chemotherapy-naive bladder cancer. This feature might help personalize neoadjuvant chemotherapy.

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BACKGROUND Raf-1 kinase inhibitor protein (RKIP) has emerged as a significant metastatic suppressor in a variety of human cancers and is known to inhibit Ras/Raf/MEK/ERK signaling. By suppressing the activation of the NFkB/SNAIL circuit, RKIP can regulate the induction of epithelial-mesenchymal transition (EMT). The aim of this study was to evaluate RKIP expression and to determine its association with clinicopathological features, including EMT in form of tumor budding in pancreatic ductal adenocarcinoma (PDAC). METHODS Staining for RKIP was performed on a multipunch Tissue Microarray (TMA) of 114 well-characterized PDACs with clinico-pathological, follow-up and adjuvant therapy information. RKIP-expression was assessed separately in the main tumor body and in the tumor buds. Another 3 TMAs containing normal pancreatic tissue, precursor lesions (Pancreatic Intraepithelial Neoplasia, PanINs) and matched lymph node metastases were stained in parallel. Cut-off values were calculated by receiver operating characteristic (ROC) curve analysis. RESULTS We found a significant progressive loss of RKIP expression between normal pancreatic ductal epithelia (average: 74%), precursor lesions (PanINs; average: 37%), PDAC (average 20%) and lymph node metastases (average 8%, p<0.0001). RKIP expression was significantly lower in tumor buds (average: 6%) compared to the main tumor body (average 20%; p<0.005). RKIP loss in the tumor body was marginally associated with advanced T-stage (p=0.0599) as well as high-grade peritumoral (p=0.0048) and intratumoral budding (p=0.0373). RKIP loss in the buds showed a clear association with advanced T stage (p=0.0089). CONCLUSIONS The progressive loss of RKIP seems to play a major role in the neoplastic transformation of pancreas, correlates with aggressive features in PDAC and is associated with the presence of EMT in form of tumor budding.