375 resultados para Malignant Myoepithelioma
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Background: Synovial sarcoma (SS) is a malignant soft tissue sarcoma with a poor prognosis because of late local recurrence and distant metastases. To our knowledge, no studies have minimum follow-up of 10 years that evaluate long-term outcomes for survivors. Patients and methods: Data on 62 patients who had been treated for SS from 1968 to 1999 were studied retrospectively in a multicenter study. Mean follow-up of living patients was 17.2 years and of dead patients 7.7 years. Results: Mean age at diagnosis was 35.4 years (range 6-82 years). Overall survival was 38.7%. The 5-year survival was 74.2%; 10-year survival was 61.2%; and 15-year survival was 46.5%. Fifteen patients (24%) died of disease after 10 years of follow-up. Local recurrence occurred after a mean of 3.6 years (range 0.5-14.9 years) and metastases at a mean of 5.7 years (range 0.5-16.3 years). Only four patients were treated technically correctly with a planned biopsy followed by a wide resection or amputation. Factors associated with significantly worse prognosis included larger tumor size, metastases at the time of diagnosis, high-grade histology, trunk-related disease, and lack of wide resection as primary surgical treatment. Conclusions: In SS, metastases develop late with high mortality. Patients with SS should be followed for >10 years.
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Immunotherapy is a promising means to fight cancer, prompting a steady increase in clinical trials and correlative laboratory studies in this field. As antitumor T cells play central roles in immunity against malignant diseases, most immunotherapeutic protocols aim to induce and/or strengthen their function. Various treatment strategies have elicited encouraging clinical responses; however, major challenges have been uncovered that should be addressed in order to fully exploit the potential of immunotherapy. Here, we outline pitfalls for the mobilization of antitumor T cells and offer solutions to improve their therapeutic efficacy. We provide a critical perspective on the main methodologies used to characterize T-cell responses to cancer therapies, with a focus on discrepancies between T-cell attributes measured in vitro and protective responses in vivo. This review altogether provides recommendations to optimize the design of future clinical trials and highlights important considerations for the proficient analysis of clinical specimens available for research.
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Brain tumors, benign or malignant, are characterized by a very high degree of vascularization. Recent accumulating evidence suggests that during development the neuronal wiring follows the same routes as the vasculature and that these two systems may share some of the same factors for guidance. Thus, expression of dual angiogenic/neurogenic growth factors was evaluated by in situ hybridization in human primary brain tumors of three different types, i.e., astrocytomas, oligodendrogliomas, and ependymomas, of increasing grades, in relation with the grade and type of the tumor. For this evaluation we selected vascular endothelial growth factor (VEGF-A) and its receptors VEGF-R1 and VEGF-R2 and the neuropilins 1 and 2 (NRP-1 and NRP-2), which have proangiogenic properties, platelet-derived growth factor (PDGF) receptor-beta (PDGF-Rβ), which is required for the functional maturation of blood vessels, the ephrins and their Eph receptors, angiotensinogen (AGT) and thrombospondin-2 (TSP-2), which have potential antiangiogenic properties, and netrin-1 (Net-1), which regulates vascular architecture. We show that the expression of the VEGF-NRP system, PDGF-Rβ, TSP-2, AGT, and Net-1 are differentially regulated, either increased or decreased, in relation with the type and grade of the tumor, whereas regulation of the ephrinB system does not seem to be relevant in these human brain tumors.
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Glioblastomas are the most malignant gliomas with median survival times of only 15 months despite modern therapies. All standard treatments are palliative. Pathogenetic factors are diverse, hence, stratified treatment plans are warranted considering the molecular heterogeneity among these tumors. However, most patients are treated with "one fits all" standard therapies, many of them with minor response and major toxicities. The integration of clinical and molecular information, now becoming available using new tools such as gene arrays, proteomics, and molecular imaging, will take us to an era where more targeted and effective treatments may be implemented. A first step towards the design of such therapies is the identification of relevant molecular mechanisms driving the aggressive biological behavior of glioblastoma. The accumulation of diverse aberrations in regulatory processes enables tumor cells to bypass the effects of most classical therapies available. Molecular alterations underlying such mechanisms comprise aberrations on the genetic level, such as point mutations of distinct genes, or amplifications and deletions, while others result from epigenetic modifications such as aberrant methylation of CpG islands in the regulatory sequence of genes. Epigenetic silencing of the MGMT gene encoding a DNA repair enzyme was recently found to be of predictive value in a randomized clinical trial for newly diagnosed glioblastoma testing the addition of the alkylating agent temozolomide to standard radiotherapy. Determination of the methylation status of the MGMT promoter may become the first molecular diagnostic tool to identify patients most likely to respond that will allow individually tailored therapy in glioblastoma. To date, the test for the MGMT-methylation status is the only tool available that may direct the choice for alkylating agents in glioblastoma patients, but many others may hopefully become part of an arsenal to stratify patients to respective targeted therapies within the next years.
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The reactivity spectrum of three monoclonal antibodies (Mabs) to human malignant glioma, five Mabs to melanomas and one Mab anti-HLA-DR was investigated by an indirect antibody binding radioimmunoassay on a panel of cells derived from 60 glioma lines, including 47 malignant astrocytomas, 11 low-grade astrocytomas and two malignant ependymomas as well on cells from 12 melanoma, three neuroblastoma, three medulloblastoma, two schwannoma, two retinoblastoma, two choroïd plexus papilloma, ten meningioma and 12 unrelated tumor lines. The anti-glioma Mabs BF7 and GE2 reacted preferentially with gliomas, while the anti-glioma Mab CG12 reacted with gliomas, melanomas, neuroblastomas and medulloblastomas. The five anti-melanoma Mabs reacted with gliomas, neuroblastomas and medulloblastomas. The anti-HLA-DR Mab D1-12 reacted with gliomas, melanomas and some meningiomas. On the basis of the data presented, we describe three different antigenic systems; the first one is glioma-associated, the second one is related to differentiation antigens expressed on cells derived from the neuroectoderm and the third is represented by HLA-DR antigens which are expressed not only on B-lymphoblastoid cells but also on melanomas and gliomas.
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Melanoma is an aggressive disease with few standard treatment options. The conventional classification system for this disease is based on histological growth patterns, with division into four subtypes: superficial spreading, lentigo maligna, nodular, and acral lentiginous. Major limitations of this classification system are absence of prognostic importance and little correlation with treatment outcomes. Recent preclinical and clinical findings support the notion that melanoma is not one malignant disorder but rather a family of distinct molecular diseases. Incorporation of genetic signatures into the conventional histopathological classification of melanoma has great implications for development of new and effective treatments. Genes of the mitogen-associated protein kinase (MAPK) pathway harbour alterations sometimes identified in people with melanoma. The mutation Val600Glu in the BRAF oncogene (designated BRAF(V600E)) has been associated with sensitivity in vitro and in vivo to agents that inhibit BRAF(V600E) or MEK (a kinase in the MAPK pathway). Melanomas arising from mucosal, acral, chronically sun-damaged surfaces sometimes have oncogenic mutations in KIT, against which several inhibitors have shown clinical efficacy. Some uveal melanomas have activating mutations in GNAQ and GNA11, rendering them potentially susceptible to MEK inhibition. These findings suggest that prospective genotyping of patients with melanoma should be used increasingly as we work to develop new and effective treatments for this disease.
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The CD44 adhesion receptor is silenced in highly malignant neuroblastomas (NBs) with MYCN amplification. Because its functional expression is associated with decreased tumorigenic properties, CD44 behaves as a tumor suppressor gene in NB and other cancers. Given that the precise mechanisms responsible for CD44 silencing are not elucidated, we investigated whether CD44 expression could be regulated by DNA hypermethylation. The methylation status of CD44 gene promoter and exon 1 regions was analyzed in 12 NB cell lines and 21 clinical samples after bisulfite genomic modification, followed by PCR and single-strand conformation polymorphism analysis and genomic sequencing. The results showed that almost all CD44-negative cell lines displayed hypermethylation in both regions, whereas all CD44-expressing cell lines were unmethylated. These observations correlated with the ability to restore CD44 mRNA and protein expression by treatment of CD44-negative cells with the 5-aza-2'-deoxycytidine demethylating agent. In contrast, no CD44 gene hypermethylation could be detected in 21 NB clinical samples of different stages, irrespective of CD44 expression. Although our results suggest that aberrant methylation of promoter and exon 1 regions is involved in CD44 silencing in NB cell lines, they also indicate that methylation of unidentified regulatory sequences or methylation-independent mechanisms also control the expression of CD44 in primary NB tumors and cell lines. We therefore conclude that CD44 silencing is controlled by complex and tumor cell-specific processes, including gene hypermethylation. Further investigation of other mechanisms and genes involved in CD44 regulation will be needed before demethylation-mediated reactivation of the CD44 gene can be considered as therapeutic strategy for neuroblastoma and perhaps other related cancers.
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To investigate a recently developed lymphadenopathy can be simple or complex. The medical history, presence or not of symptoms, the general physical examination, and the localization and characteristics of the adenopathy, most often lead to a diagnosis and therapy when indicated. Among young adults, the etiology is either infectious or reactive, rarely tumoral, as opposed to elderly persons. The most important step is to look at signs of severity (or non banality) such as an increased size, hard consistency, supra-clavicular location, an immunocompromised host, a history of Tb exposition. If present, these signs will trigger a biopsy with cyto- or histopathological examination mostly to rule out a malignant tumor. This article reviews the practical steps of an investigation of an isolated adenopathy in an adult patient.
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SUMMARY Radiotherapy is commonly and efficiently used to treat solid cancer in the clinic. Experimental evidence however suggests that radiation can promote tumor progression by inducing chronic modifications of the tumor microenvironment. Clinically, these observations are highly relevant to aggressive tumoral lesions relapsing after radiation therapy, a leading cause of patients' death. The investigation and understanding of the biological mechanisms implicated in the malignant progression of post-radiation relapses are therefore of major importance. Here we used a syngeneic (immunocompetent) breast cancer orthotopic xenograft model, to show that local irradiation of the mammary gland promotes the appearance of an invasive and metastatic tumor phenotype. Previous studies in our laboratory revealed that inhibition of tumor-induced angiogenesis and consequent increase in tumor hypoxia promotes metastasis formation through the activation of pro-invasive programs in the tumor cells. Our results extend these observations suggesting that mammary gland irradiation induces the recruitment of CD11b+ cells to both the primary tumor and the lungs at pre-metastatic stages through the hypoxia-dependent induction of Kit-ligand (KITL) expression in primary tumors. Abrogation of KITL expression in tumor cells prevented CD11 b+ cells accumulation in both the primary tumor and lungs and significantly reduced metastases of tumors growing in irradiated mammary gland. Importantly, irradiated mammary gland enhanced tumor-induced mobilization of circulating CD11b+cKit+ myelomonocytic cells through a HIF1- and KITL-dependent process. By cell transfer experiments, mobilized circulating CD11b+cKit+ cells were shown to supply both tumor- and lungs infiltrating CD11b+ cells. Using a blocking antibody against cKit (the KITL receptor), the mobilization of CD11b+cKit+ ceils was prevented as well as lung metastases derived from tumors growing in irradiated mammary gland. Taken together, these results indicate that tumors growing in a pre-irradiated mammary gland partially promote their malignant progression through the distant mobilization of circulating myelomonocytic precursor cells. They identify KITL inhibition and/or cKit receptor neutralization as potentially promising therapeutic approaches for post-radiation relapses. RESUME La radiothérapie est largement utilisée comme traitement de choix de nombreux types de cancers. L'agressivité des récidives tumorales observée en clinique après radiothérapie suggère cependant que le recours à l'irradiation pourrait dans certains cas accélérer la progression tumorale. De récents travaux expérimentaux ont en effet permis d'appuyer cette hypothèse, en montrant notamment l'effet néfaste des modifications chroniques de l'environnement induites par l'irradiation sur la progression tumorale. A l'aide d'un modèle murin syngénique orthotopique de cancer de sein, nous avons pu montrer que l'irradiation locale de la glande mammaire facilite l'invasion et la dissémination métastatique des cellules tumorales en favorisant le recrutement de cellules myéloïdes CD11 b+ vers la tumeur primaire et les poumons à un stade pré-métastatique. Comme mécanisme impliqué dans le recrutement des cellules CD11b+, nous avons pu observer après irradiation locale de la glande mammaire une expression augmentée de Kit-ligand (KITL) dans la tumeur (induite par l'hypoxie) ainsi que la mobilisation de cellules myéloïdes circulantes exprimant le récepteur cKit et précurseurs des cellules CD11b+ infiltrant la tumeur et les poumons. En empêchant la mobilisation par la tumeur de cellules circulantes cKit+ par des approches à la fois génétique et pharmacologique nous avons pu prévenir l'accumulation de cellules myéloïdes CD11 b+ dans la tumeur primaire et les poumons ainsi que la dissémination métastatique induites par' l'irradiation de la glande mammaire. De façon générale, ces résultats montrent que la progression agressive des tumeurs qui se développent dans un environnement irradié repose à la fois sur l'expression tumorale de KITL et la mobilisation de cellules myéloïdes précurseurs cKit*. Ils auront permis d'identifier KITL et/ou cKit comme des cibles thérapeutiques potentielles intéressantes pour le traitement des récidives tumorales après radiothérapie.
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The incidence of contralateral breast cancer is high and constant with age, around five per 1000 women who had a primary breast cancer. For other neoplasms, the pattern of incidence of second primary neoplasms with age is less known, particularly as for only a few neoplasms the site of origin is not totally removed, and hence remains at risk of a second primary. Using the dataset from the Cancer Registry of the Swiss Canton of Vaud, we show that the incidence of second neoplasms is constant with age also after oral and pharyngeal, colorectal cancers, cutaneous malignant melanoma (CMM) and basal cell carcinoma. The incidence of first primary oral and pharyngeal cancer increased 20-fold between age 30-39 and 70-89 years, whereas the incidence of second neoplasms did not increase with age. Rates of second colorectal cancer remained relatively constant with age, between 2.5 per 1000 at age 40-59 years and 3.8 per 1000 at 70 years and above. Likewise, for CMM, the age-specific incidence rates of second primary CMM did not vary, ranging between 1 and 2.5 per 1000 in various subsequent age groups. The pattern of incidence for second basal cell carcinoma was similar, with no clear rise with age. These patterns are compatible with the occurrence of a single mutational event in a population of susceptible individuals. A possible implication of these observations is that a variable, but potentially large, proportion of cancers arise in very high-risk individuals and the incidence, on average, increases at a high constant level at a predetermined age.
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PURPOSE: To remind of the absolute necessity for early diagnosis in the presence of ocular signs in children giving rise to possible intraocular tumours. METHOD: Based on our own experience of intraocular tumours in children, together with findings from the literature, diagnostic criteria and methods of treatment are presented. RESULTS: Retinoblastoma is the predominant cause of intraocular tumours in children, representing over 80% of cases under the age of 15 years. Other diseases may give rise to the same initial signs, usually leukocoria, sometimes strabismus, more rarely other atypical signs. Elements taken into account for diagnosis include age, sex, laterality, heredity, size of the globe, clinical aspect of the tumours, presence of calcifications and vitreous seeding. Full fundus examination under general anaesthetic is usually necessary. Biological examination, ultrasonography, computerized tomography and MRI enable an accurate diagnosis to be made in the majority of doubtful cases. The management of retinoblastoma is adapted for each individual case from the wide range of treatments available. Enucleation, radioactive applicators (...), brachytherapy (...), cryo- and photocoagulation represent classical measures. Primary chemotherapy, combined with other treatments such as thermotherapy, has become the treatment of choice in those cases where external beam radiotherapy has been used up to now, or in some instances before enucleation. Enucleation is usually carried out for medullo-epitheliomas, but brachytherapy may offer an alternative. CONCLUSION: Any unexplained ocular sign in children should be considered as a possible retinoblastoma, making an accurate and certain diagnosis imperative. Early treatment may save not only the life but also the vision of patients carrying this highly malignant lesion.
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Significant progress has been made in the molecular diagnostic subtyping of brain tumors, in particular gliomas. In contrast to the classical molecular markers in this field, p53 and epidermal growth factor receptor (EGFR) status, the clinical significance of which has remained controversial, at least three important molecular markers with clinical implications have now been identified: 1p/19q codeletion, O⁶-methylguanine methyltransferase (MGMT) promoter methylation and isocitrate dehydrogenase-1 (IDH1) mutations. All three are favorable prognostic markers. 1p/19q codeletion and IDH1 mutations are also useful to support and extend the histological classification of gliomas since they are strongly linked to oligodendroglial morphology and grade II/III gliomas, as opposed to glioblastoma, respectively. MGMT promoter methylation is the only potentially predictive marker, at least for alkylating agent chemotherapy in glioblastoma. Beyond these classical markers, the increasing repertoire of anti-angiogenic agents that are currently explored within registration trials for gliomas urgently calls for efforts to identify molecular markers that predict the benefit derived from these novel treatments, too.
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The function of antigen-specific CD8+ T cells, which may protect against both infectious and malignant diseases, can be impaired by ligation of their inhibitory receptors, which include CTL-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1). Recently, B and T lymphocyte attenuator (BTLA) was identified as a novel inhibitory receptor with structural and functional similarities to CTLA-4 and PD-1. BTLA triggering leads to decreased antimicrobial and autoimmune T cell responses in mice, but its functions in humans are largely unknown. Here we have demonstrated that as human viral antigen-specific CD8+ T cells differentiated from naive to effector cells, their surface expression of BTLA was gradually downregulated. In marked contrast, human melanoma tumor antigen-specific effector CD8+ T cells persistently expressed high levels of BTLA in vivo and remained susceptible to functional inhibition by its ligand herpes virus entry mediator (HVEM). Such persistence of BTLA expression was also found in tumor antigen-specific CD8+ T cells from melanoma patients with spontaneous antitumor immune responses and after conventional peptide vaccination. Remarkably, addition of CpG oligodeoxynucleotides to the vaccine formulation led to progressive downregulation of BTLA in vivo and consequent resistance to BTLA-HVEM-mediated inhibition. Thus, BTLA activation inhibits the function of human CD8+ cancer-specific T cells, and appropriate immunotherapy may partially overcome this inhibition.
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Standard care for newly diagnosed glioblastoma multiforme (GBM) previously consisted of resection to the greatest extent feasible, followed by radiotherapy. The role of chemotherapy was controversial and its efficacy was marginal at best. Five years ago temozolomide (TMZ) was approved specifically for the treatment of recurrent malignant glioma. The role of TMZ chemotherapy administered alone or as an adjuvant therapy for newly diagnosed GBM has been evaluated in a large randomized trial whose results suggested a significant prolongation of survival following treatment. Findings of correlative molecular studies have indicated that methylguanine methyltransferase promoter methylation may be used as a predictive factor in selecting patients most likely to benefit from such treatment. In this short review the authors summarize the current role of TMZ chemotherapy in the management of GBM, with an emphasis on approved indications and practical aspects.
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BACKGROUND: The purpose of this study was to explore the potential use of image analysis on tissue sections preparation as a predictive marker of early malignant changes during squamous cell (SC) carcinogenesis in the esophagus. Results of DNA ploidy quantification on formalin-fixed, paraffin-embedded tissue using two different techniques were compared: imprint-cytospin and 6 microm thick tissue sections preparation. METHODS: This retrospective study included 26 surgical specimens of squamous cell carcinoma (SCC) from patients who underwent surgery alone at the Department of Surgery in CHUV Hospital in Lausanne between January 1993 and December 2000. We analyzed 53 samples of healthy tissue, 43 tumors and 7 lymph node metastases. RESULTS: Diploid DNA histogram patterns were observed in all histologically healthy tissues, either distant or proximal to the lesion. Aneuploidy was observed in 34 (79%) of 43 carcinomas, namely 24 (75%) of 32 early squamous cell carcinomas and 10 (91%) of 11 advanced carcinomas. DNA content was similar in the different tumor stages, whether patients presented with single or multiple synchronous tumors. All lymph node metastases had similar DNA content as their primary tumor. CONCLUSIONS: Early malignant changes in the esophagus are associated with alteration in DNA content, and aneuploidy tends to correlate with progression of invasive SCC. A very good correlation between imprint-cytospin and tissue section analysis was observed. Although each method used here showed advantages and disadvantages; tissue sections preparation provided useful information on aberrant cell-cycle regulation and helped select the optimal treatment for the individual patient along with consideration of other clinical parameters.