988 resultados para Malignant neoplasm


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Mode of access: Internet.

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Between 1993 and 2001, 106 patients with esophageal cancer were reviewed at a multidisciplinary clinic and treated with palliative intent by chemoradiation therapy. This study assesses the palliative benefit on dysphagia and documents the toxicity of this treatment. The study population comprised 72 men and 34 women with a median age of 69 years. Patients were treated with a median radiation dose of 35 Gy in 15 fractions with a concurrent single course of 5 FU-based chemotherapy. Dysphagia was measured at the beginning and completion of treatment and at monthly intervals until death, using a modified DeMeester (4-point) score. Treatment was well tolerated, with only 5% of patients failing to complete therapy. The treatment-related mortality was 6%. The median survival for the study population was 7 months. The median baseline score at presentation was 2 (difficulty with soft food). Following treatment, 49% of patients were assessed as having a dysphagia score of 0 (no dysphagia). Seventy-eight per cent had an improvement of at least one grade in their dysphagia score after treatment. Only 14% of patients showed no improvement with treatment. Fifty-one per cent maintained improved swallowing until the time of last follow-up or death. This single-institution study shows that chemoradiation therapy administered for the palliation of malignant dysphagia is well tolerated and produces a sustainable normalization in swallowing for almost half of all patients.

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Aims: To analyse the expression of proteins involved in DNA double strand break detection and repair in the luminal and myoepithelial compartments of benign breast lesions and malignant breast tumours with myoepithelial differentiation. Methods: Expression of the ataxia telangiectasia (ATM) and p53 proteins was immunohistochemically evaluated in 18 benign and malignant myoepithelial tumours of the breast. Fifteen benign breast lesions with prominent myoepithelial compartment were also evaluated for these proteins, in addition to those in the MRE11-Rad50-NBS1 (MRN) complex, and the expression profiles were compared with those seen in eight independent non-cancer (normal breast) samples and in the surrounding normal tissues of the benign and malignant tumours examined. Results: ATM expression was higher in the myoepithelial compartment of three of 15 benign breast lesions and lower in the luminal compartment of eight of these lesions compared with that found in the corresponding normal tissue compartments. Malignant myoepithelial tumours overexpressed ATM in one of 18 cases. p53 was consistently negative in benign lesions and was overexpressed in eight of 18 malignant tumours. In benign breast lesions, expression of the MRN complex was significantly more reduced in myoepithelial cells (up to 73%) than in luminal cells (up to 40%) (p = 0.0005). Conclusions: Malignant myoepithelial tumours rarely overexpress ATM but are frequently positive for p53. In benign breast lesions, expression of the MRN complex was more frequently reduced in the myoepithelial than in the luminal epithelial compartment, suggesting different DNA repair capabilities in these two cell types.

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Purpose: To describe the surgical technique and results of en bloc excision in a series of patients with extensive malignant tumors of the lacrimal drainage apparatus (LDA). Methods: This was a noncomparative, retrospective chart review of the clinical and pathologic findings of 11 patients presenting with a malignant tumor affecting the LDA who underwent en bloc excision of the lacrimal system. Results: Of the 11 patients, 7 were male. The mean age at presentation was 58 years (range, 39 to 81 years), and all cases were unilateral. Histopathology revealed 4 squamous cell carcinomas, 3 transitional cell carcinomas, 2 mucoepidermoid carcinomas, and 2 melanomas. Epiphora and a mass were the most common presentations. An external lesion could be identified in 4 cases. Irrigation of the lacrimal system revealed nasolacrimal duct obstruction in 2 cases and common canaliculus obstruction in another 2 patients. The entire LDA and surrounding bony tissues were excised through a lateral rhinotomy approach. Adjuvant radiotherapy was given in 4 cases. Nine patients remain alive and well after a mean follow-up of 2 years (range, 6 months to 7 years). Three cases showed distant disease and 2 patients died of metastatic melanoma involvement. Conclusions: The use of en bloc excision as a radical treatment to remove the complete LDA and surrounding bony structures affords good local tumor control and may provide the best opportunity for enhanced patient survival.

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The purpose of this study was to investigate the effects of 17-β-estradiol (E2)-induced reactive oxygen species (ROS) on the induction of mammary tumorigenesis. We found that ROS-induced by repeated exposures to 4-hydroxy-estradiol (4-OH-E2), a predominant catechol metabolite of E2, caused transformation of normal human mammary epithelial MCF-10A cells with malignant growth in nude mice. This was evident from inhibition of estrogen-induced breast tumor formation in the xenograft model by both overexpression of catalase as well as by co-treatment with Ebselen. To understand how 4-OH-E2 induces this malignant phenotype through ROS, we investigated the effects of 4-OH-E2 on redox-sensitive signal transduction pathways. During the malignant transformation process we observed that 4-OH-E2 treatment increased AKT phosphorylation through PI3K activation. The PI3K-mediated phosphorylation of AKT in 4-OH-E2-treated cells was inhibited by ROS modifiers as well as by silencing of AKT expression. RNA interference of AKT markedly inhibited 4-OH-E2-induced in vitro tumor formation. The expression of cell cycle genes, cdc2, PRC1 and PCNA and one of transcription factors that control the expression of these genes – nuclear respiratory factor-1 (NRF-1) was significantly up-regulated during the 4-OH-E2-mediated malignant transformation process. The increased expression of these genes was inhibited by ROS modifiers as well as by silencing of AKT expression. These results indicate that 4-OH-E2-induced cell transformation may be mediated, in part, through redox-sensitive AKT signal transduction pathways by up-regulating the expression of cell cycle genes cdc2, PRC1 and PCNA, and the transcription factor – NRF-1. In summary, our study has demonstrated that: (i) 4-OH-E2 is one of the main estrogen metabolites that induce mammary tumorigenesis and (ii) ROS-mediated signaling leading to the activation of PI3K/AKT pathway plays an important role in the generation of 4-OH-E2-induced malignant phenotype of breast epithelial cells. In conclusion, ROS are important signaling molecules in the development of estrogen-induced malignant breast lesions.

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Background: Myeloproliferative neoplasms (MPNs) including the classic entities; polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis are rare diseases with unknown aetiology. The MOSAICC study, is an exploratory case–control study in which information was collected through telephone questionnaires and medical records. Methods: As part of the study, 106 patients with MPN were asked about their perceived diagnosis and replies correlated with their haematologist’s diagnosis. For the first time, a patient perspective on their MPN diagnosis and classification was obtained. Logistic regression analyses were utilised to evaluate the role of variables in whether or not a patient reported their diagnosis during interview with co-adjustment for these variables. Chi square tests were used to investigate the association between MPN subtype and patient reported categorisation of MPN. Results: Overall, 77.4 % of patients reported a diagnosis of MPN. Of those, 39.6 % recognised MPN as a ‘blood condition’,23.6 % recognised MPN as a ‘cancer’ and 13.2 % acknowledged MPN as an ‘other medical condition’. There was minimal overlap between the categories. Patients with PV were more likely than those with ET to report their disease as a ‘blood condition’. ET patients were significantly more likely than PV patients not to report their condition at all.Patients from a single centre were more likely to report their diagnosis as MPN while age, educational status, and WHO re-classification had no effect. Conclusions: The discrepancy between concepts of MPN in patients could result from differing patient interest in their condition, varying information conveyed by treating hematologists, concealment due to denial or financial concerns. Explanations for the differences in patient perception of the nature of their disease, requires further, larger scale investigation.

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Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue neoplasm of intermediate biologic potential and uncertain differentiation, most often arising in the extremities of children and young adults. Although it has characteristic histologic features of a lymphoid cuff surrounding nodules of ovoid cells with blood-filled cystic cavities, diagnosis is often difficult due to its morphologic heterogeneity and lack of specific immunoprofile. Angiomatoid fibrous histiocytoma is associated with recurrent chromosomal translocations, leading to characteristic EWSR1-CREB1, EWSR1-ATF1, and, rarely, FUS-ATF1 gene fusions; fluorescence in situ hybridization (FISH), detecting EWSR1 or FUS rearrangements, and reverse transcription-polymerase chain reaction (RT-PCR) for EWSR1-CREB1 and EWSR1-ATF1 fusion transcripts have become routine ancillary tools. We present a large comparative series of FISH and RT-PCR for AFH. Seventeen neoplasms (from 16 patients) histologically diagnosed as AFH were assessed for EWSR1 rearrangements or EWSR1-CREB1 and EWSR1-ATF1 fusion transcripts. All 17 were positive for either FISH or RT-PCR or both. Of 16, 14 (87.5%) had detectable EWSR1-CREB1 or EWSR1-ATF1 fusion transcripts by RT-PCR, whereas 13 (76.5%) of 17 had positive EWSR1 rearrangement with FISH. All 13 of 13 non-AFH control neoplasms failed to show EWSR1-CREB1 or EWSR1-ATF1 fusion transcripts, whereas EWSR1 rearrangement was present in 2 of these 13 cases (which were histopathologically myoepithelial neoplasms). This study shows that EWSR1-CREB1 or EWSR1-ATF1 fusions predominate in AFH (supporting previous reports that FUS rearrangement is rare in AFH) and that RT-PCR has a comparable detection rate to FISH for AFH. Importantly, cases of AFH can be missed if RT-PCR is not performed in conjunction with FISH, and RT-PCR has the added advantage of specificity, which is crucial, as EWSR1 rearrangements are present in a variety of neoplasms in the histologic differential diagnosis of AFH, that differ in behavior and treatment.

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The pathogenesis of diffuse large B-cell lymphoma (DLBCL) remains partially unknown. The analysis of the B-cell receptor of the malignant cells could contribute to a better understanding of the DLBCL biology. We studied the molecular features of the immunoglobulin heavy chain (IGH) rearrangements in 165 patients diagnosed with DLBCL not otherwise specified. Clonal IGH rearrangements were amplified according to the BIOMED-2 protocol and PCR products were sequenced directly. We also analyzed the criteria for stereotyped patterns in all complete IGHV-IGHD-IGHJ (V-D-J) sequences. Complete V-D-J rearrangements were identified in 130 of 165 patients. Most cases (89%) were highly mutated, but 12 sequences were truly unmutated or minimally mutated. Three genes, IGHV4-34, IGHV3-23, and IGHV4-39, accounted for one third of the whole cohort, including an overrepresentation of IGHV4-34 (15.5% overall). Interestingly, all IGHV4-34 rearrangements and all unmutated sequences belonged to the nongerminal center B-cell-like (non-GCB) subtype. Overall, we found three cases following the current criteria for stereotyped heavy chain VH CDR3 sequences, two of them belonging to subsets previously described in CLL. IGHV gene repertoire is remarkably biased, implying an antigen-driven origin in DLBCL. The particular features in the sequence of the immunoglobulins suggest the existence of particular subgroups within the non-GCB subtype.

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Clinical outcome following chemotherapy for malignant pleural mesothelioma is poor and improvements are needed. This preclinical study investigates the effect of five tyrosine kinase inhibitors (PTK787, ZD6474, ZD1839, SU6668 and SU11248) on the growth of three mesothelioma cell lines (NCI H226, NCI H28 and MSTO 211H), the presence of growth factor receptors and inhibition of their downstream signalling pathways. GI50 values were determined: ZD6474 and SU11248, mainly VEGFR2 inhibitors, gave the lowest GI50 across all cell lines (3.5-6.9 microM) whereas ZD1839 gave a GI50 in this range only in H28 cells. All cell lines were positive for EGFR, but only H226 cells were positive for VEGFR2 by Western blotting. ZD6474 and ZD1839 inhibited EGF-induced phosphorylation of EGFR, AKT and ERK, whereas VEGF-induced phosphorylation of VEGFR2 was completely inhibited with 0.1 microM SU11248. VEGFR2 was detected in tumour samples by immunohistochemistry. VEGFR2 tyrosine kinase inhibitors warrant further investigation in mesothelioma.

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To define specific pathways important in the multistep transformation process of normal plasma cells (PCs) to monoclonal gammopathy of uncertain significance (MGUS) and multiple myeloma (MM), we have applied microarray analysis to PCs from 5 healthy donors (N), 7 patients with MGUS, and 24 patients with newly diagnosed MM. Unsupervised hierarchical clustering using 125 genes with a large variation across all samples defined 2 groups: N and MGUS/MM. Supervised analysis identified 263 genes differentially expressed between N and MGUS and 380 genes differentially expressed between N and MM, 197 of which were also differentially regulated between N and MGUS. Only 74 genes were differentially expressed between MGUS and MM samples, indicating that the differences between MGUS and MM are smaller than those between N and MM or N and MGUS. Differentially expressed genes included oncogenes/tumor-suppressor genes (LAF4, RB1, and disabled homolog 2), cell-signaling genes (RAS family members, B-cell signaling and NF-kappaB genes), DNA-binding and transcription-factor genes (XBP1, zinc finger proteins, forkhead box, and ring finger proteins), and developmental genes (WNT and SHH pathways). Understanding the molecular pathogenesis of MM by gene expression profiling has demonstrated sequential genetic changes from N to malignant PCs and highlighted important pathways involved in the transformation of MGUS to MM.