422 resultados para breast screening


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Recent evidence indicates that the estrogen receptor-a-negative, androgen receptor (AR)- positive molecular apocrine subtype of breast cancer is driven by AR signaling. The MDA-MB-453 cell line is the prototypical model of this breast cancer subtype; its proliferation is stimulated by androgens such as 5a-dihydrotestosterone (DHT) but inhibited by the progestin medroxyprogesterone acetate (MPA) via AR-mediated mechanisms. We report here that the AR gene in MDAMB- 453 cells contains a G-T transversion in exon 7, resulting in a receptor variant with a glutamine to histidine substitution at amino acid 865 (Q865H) in the ligand binding domain. Compared with wild-type AR, the Q865H variant exhibited reduced sensitivity to DHT and MPA in transactivation assays in MDA-MB-453 and PC-3 cells but did not respond to non-androgenic ligands or receptor antagonists. Ligand binding, molecular modeling, mammalian two-hybrid and immunoblot assays revealed effects of the Q865H mutation on ligand dissociation, AR intramolecular interactions, and receptor stability. Microarray expression profiling demonstrated that DHT and MPA regulate distinct transcriptional programs in MDA-MB-453 cells. Gene Set Enrichment Analysis revealed that DHT- but not MPA-regulated genes were associated with estrogen-responsive transcriptomes from MCF-7 cells and the Wnt signaling pathway. These findings suggest that the divergent proliferative responses of MDA-MB-453 cells to DHT and MPA result from the different genetic programs elicited by these two ligands through the AR-Q865H variant. This work highlights the necessity to characterize additional models of molecular apocrine breast cancer to determine the precise role of AR signaling in this breast cancer subtype. Endocrine-Related Cancer (2012) 19 599–613

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Highly sensitive infrared cameras can produce high-resolution diagnostic images of the temperature and vascular changes of breasts. Wavelet transform based features are suitable in extracting the texture difference information of these images due to their scale-space decomposition. The objective of this study is to investigate the potential of extracted features in differentiating between breast lesions by comparing the two corresponding pectoral regions of two breast thermograms. The pectoral regions of breastsare important because near 50% of all breast cancer is located in this region. In this study, the pectoral region of the left breast is selected. Then the corresponding pectoral region of the right breast is identified. Texture features based on the first and the second sets of statistics are extracted from wavelet decomposed images of the pectoral regions of two breast thermograms. Principal component analysis is used to reduce dimension and an Adaboost classifier to evaluate classification performance. A number of different wavelet features are compared and it is shown that complex non-separable 2D discrete wavelet transform features perform better than their real separable counterparts.

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The most integrated approach toward understanding the multiple molecular events and mechanisms by which cancer may develop is the application of gene expression profiling using microarray technologies. As molecular alterations in breast cancer are complex and involve cross-talk between multiple cellular signalling pathways, microarray technology provides a means of capturing and comparing the expression patterns of the entire genome across multiple samples in a high throughput manner. Since the development of microarray technologies, together with the advances in RNA extraction methodologies, gene expression studies have revolutionised the means by which genes suitable as targets for drug development and individualised cancer treatment can be identified. As of the mid-1990s, expression microarrays have been extensively applied to the study of cancer and no cancer type has seen as much genomic attention as breast cancer. The most abundant area of breast cancer genomics has been the clarification and interpretation of gene expression patterns that unite both biological and clinical aspects of tumours. It is hoped that one day molecular profiling will transform diagnosis and therapeutic selection in human breast cancer toward more individualised regimes. Here, we review a number of prominent microarray profiling studies focussed on human breast cancer and examine their strengths, their limitations, clinical implications including prognostic relevance and gene signature significance along with potential improvements for the next generation of microarray studies.

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This study aimed to identify new peptide antigens from Chlamydia (C.) trachomatis in a proof of concept approach which could be used to develop an epitope-based serological diagnostic for C. trachomatis related infertility in women. A bioinformatics analysis was conducted examining several immunodominant proteins from C. trachomatis to identify predicted immunoglobulin epitopes unique to C. trachomatis. A peptide array of these epitopes was screened against participant sera. The participants (all female) were categorized into the following cohorts based on their infection and gynecological history; acute (single treated infection with C. trachomatis), multiple (more than one C. trachomatis infection, all treated), sequelae (PID or tubal infertility with a history of C. trachomatis infection), and infertile (no history of C. trachomatis infection and no detected tubal damage). The bioinformatics strategy identified several promising epitopes. Participants who reacted positively in the peptide 11 ELISA were found to have an increased likelihood of being in the sequelae cohort compared to the infertile cohort with an odds ratio of 16.3 (95% c.i. 1.65 – 160), with 95% specificity and 46% sensitivity (0.19-0.74). The peptide 11 ELISA has the potential to be further developed as a screening tool for use during the early IVF work up and provides proof of concept that there may be further peptide antigens which could be identified using bioinformatics and screening approaches.

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Stress corrosion cracking (SCC) is a well known form of environmental attack in low carat gold jewellery. It is desirable to have a quick, easy and cost effective way to detect SCC in alloys and prevent them from being used and later failing in their application. A facile chemical method to investigate SCC of 9 carat gold alloys is demonstrated. It involves a simple application of tensile stress to a wire sample in a corrosive environment such as 1–10 % FeCl3 which induces failure in less than 5 minutes. In this study three quaternary (Au, Ag, Cu and Zn) 9 carat gold alloy compositions were investigated for their resistance to SCC and the relationship between time to failure and processing conditions is studied. It is envisaged that the use of such a rapid and facile screening procedure at the production stage may readily identify alloy treatments that produce jewellery that will be susceptible to SCC in its lifetime.

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Background Nutrition screening is usually administered by nurses. However, most studies on nutrition screening tools have not used nurses to validate the tools. The 3-Minute Nutrition Screening (3-MinNS) assesses weight loss, dietary intake and muscle wastage, with the composite score of each used to determine risk of malnutrition. The aim of the study was to determine the validity and reliability of 3-MinNS administered by nurses, who are the intended assessors. Methods In this cross sectional study, three ward-based nurses screened 121 patients aged 21 years and over using 3-MinNS in three wards within 24 hours of admission. A dietitian then assessed the patients’ nutritional status using Subjective Global Assessment within 48 hours of admission, whilst blinded to the results of the screening. To assess the reliability of 3-MinNS, 37 patients screened by the first nurse were re-screened by a second nurse within 24 hours, who was blinded to the results of the first nurse. The sensitivity, specificity and best cutoff score for 3-MinNS were determined using the Receiver Operator Characteristics Curve. Results The best cutoff score to identify all patients at risk of malnutrition using 3-MinNS was three, with sensitivity of 89% and specificity of 88%. This cutoff point also identified all (100%) severely malnourished patients. There was strong correlation between 3-MinNS and SGA (r=0.78, p<0.001). The agreement between two nurses conducting the 3-MinNS tool was 78.3%. Conclusion 3-Minute Nutrition Screening is a valid and reliable tool for nurses to identify patients at risk of malnutrition.

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Background Cancer-related malnutrition is associated with increased morbidity, poorer tolerance of treatment, decreased quality of life, increased hospital admissions, and increased health care costs (Isenring et al., 2013). This study’s aim was to determine whether a novel, automated screening system was a useful tool for nutrition screening when compared against a full nutrition assessment using the Patient-Generated Subjective Global Assessment (PG-SGA) tool. Methods A single site, observational, cross-sectional study was conducted in an outpatient oncology day care unit within a Queensland tertiary facility, with three hundred outpatients (51.7% male, mean age 58.6 ± 13.3 years). Eligibility criteria: ≥18 years, receiving anticancer treatment, able to provide written consent. Patients completed the Malnutrition Screening Tool (MST). Nutritional status was assessed using the PG-SGA. Data for the automated screening system was extracted from the pharmacy software program Charm. This included body mass index (BMI) and weight records dating back up to six months. Results The prevalence of malnutrition was 17%. Any weight loss over three to six weeks prior to the most recent weight record as identified by the automated screening system relative to malnutrition resulted in 56.52% sensitivity, 35.43% specificity, 13.68% positive predictive value, 81.82% negative predictive value. MST score 2 or greater was a stronger predictor of nutritional risk relative to PG-SGA classified malnutrition (70.59% sensitivity, 69.48% specificity, 32.14% positive predictive value, 92.02% negative predictive value). Conclusions Both the automated screening system and the MST fell short of the accepted professional standard for sensitivity (80%) or specificity (60%) when compared to the PG-SGA. However, although the MST remains a better predictor of malnutrition in this setting, uptake of this tool in the Oncology Day Care Unit remains challenging.

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While reviewing this book, I was not of the target audience. For example, there is a first chapter (presented as a case study, and integrated in an unconvincing manner into the remainder of the book) that obviously meant to soften the book for the lay person. In the third chapter, the authors provide their philosophical interpretation on the meaning of breasts for reasons that entirely escape me, and that have no relation to the book as a whole. Finally, there are potted histories of the heroics of ‘tireless’, ‘dedicated’ and ‘earnest’ epidemiologists, some of whom have nothing to do with breast cancer or the book at all. Despite this lack of focus, the authors give an honest and coherent account of the current state of breast cancer research from an epidemiological viewpoint...

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Cisplatin and carboplatin are active in previously untreated patients with metastatic breast cancer (MBC) with mean response rates (RRs) of 50 and 32%, respectively. In pretreated patients the RR to cisplatin/carboplatin monotherapy declines markedly to <10%. Cisplatin and carboplatin have been combined with many other cytotoxics. In first-line setting high activity has been observed in combination with taxanes or vinorelbine (RRs consistently ∼60%). It appears that these newer combinations are superior to older regimens with etoposide (RRs 30 to 50%) or 5-fluorouracil (RRs 40 to 60%). Cisplatin-/carboplatin-based regimens with infusional 5-FU and epirubicin/paclitaxel/vinorelbine achieve high RRs of around 60 to 80%. However these regimens are difficult to administer in all patients because they require central venous access for continuous 5-FU infusion. In pretreated MBC the combinations of cisplatin-taxane/vinorelbine/gemcitabine or carboplatin-docetaxel/vinorelbine yield RRs of 40 to 50%, which are higher than those achieved with platinum-etoposide/5-FU. In locally advanced disease cisplatin-based regimens achieve very high RRs (>80%). This would suggest that in chemotherapy-naïve patients platinum-based therapy might have an important role to play. Additionally the synergy demonstrated between platinum compounds, taxanes and herceptin, in preclinical and clinical studies is of immense importance and the results of the two ongoing Breast Cancer International Research Group randomized phase III studies are eagerly awaited. These studies may help clarify the role of platinum compounds in the treatment of metastatic and possibly early breast cancer. © 2003 Elsevier Ltd. All rights reserved.

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Aims: After failure of anthracycline- and taxane-based chemotherapy in metastatic breast cancer, treatment options until recently were limited. Until the introduction of capecitabine and vinorelbine, no standard regimen was available. We conducted a retrospective study to determine the efficacy and toxicity of platinum-based chemotherapy in metastatic breast cancer. Materials and methods: Forty-two women with metastatic breast cancer previously treated with anthracyclines (93%) and/or taxanes (36%) received mitomycin-vinblastine-cisplatin (MVP) (n = 23), or cisplatin-etoposide (PE) (n = 19), as first-, second- and third-line treatment at a tertiary referral centre between 1997 and 2002. Chemotherapy was given every 3 weeks as follows: mitomycin-C (8 mg/m 2) (cycles 1, 2, 4, 6), vinblastine (6 mg/m 2), and cisplatin (50 mg/m 2) all on day 1; and cisplatin (75 mg/m 2) and etoposide (100 mg/m 2) on day 1 and (100 mg/m 2) orally twice a day on days 2-3. Results: The response rate for 40 evaluable patients (MVP: n = 23; PE: n = 17) was 18% (95% confidence interval [CI]: 9-32%). The response rate to MVP was 13% (95% CI: 5-32%, one complete and two partial responses) and to PE 24% (10-47%, four partial responses). Disease stabilised in 43% (26-63%) and 47% (26-69%) of women treated with MVP and PE, respectively. After a median follow-up of 18 months, 37 women (MVP: n = 19; PE: n = 18) died from their disease. Median (range) progression-free survival and overall survival were 6 months (0.4-18.7) and 9.9 months (1.3-40.8), respectively. Median progression-free survival for the MVP and PE groups was 5.5 and 6.2 months (Log-rank, P = 0.82), and median overall survival was 10.2 and 9.4 months (Log-rank, P = 0.46), respectively. The main toxicity was myelosuppression. Grades 3-4 neutropenia was more common in women treated with PE than in women treated with MVP (74% vs 30%; P = 0.012), but the incidence of neutropenic sepsis, relative to the number of chemotherapy cycles, was low (7% overall). The toxicity-related hospitalisation rate was 1.2 admissions per six cycles of chemotherapy. No treatment-related deaths occurred. MVP and PE chemotherapy have modest activity and are safe in women with metastatic breast cancer. © 2005 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

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Early detection, clinical management and disease recurrence monitoring are critical areas in cancer treatment in which specific biomarker panels are likely to be very important in each of these key areas. We have previously demonstrated that levels of alpha-2-heremans-schmid-glycoprotein (AHSG), complement component C3 (C3), clusterin (CLI), haptoglobin (HP) and serum amyloid A (SAA) are significantly altered in serum from patients with squamous cell carcinoma of the lung. Here, we report the abundance levels for these proteins in serum samples from patients with advanced breast cancer, colorectal cancer (CRC) and lung cancer compared to healthy controls (age and gender matched) using commercially available enzyme-linked immunosorbent assay kits. Logistic regression (LR) models were fitted to the resulting data, and the classification ability of the proteins was evaluated using receiver-operating characteristic curve and leave-one-out cross-validation (LOOCV). The most accurate individual candidate biomarkers were C3 for breast cancer [area under the curve (AUC) = 0.89, LOOCV = 73%], CLI for CRC (AUC = 0.98, LOOCV = 90%), HP for small cell lung carcinoma (AUC = 0.97, LOOCV = 88%), C3 for lung adenocarcinoma (AUC = 0.94, LOOCV = 89%) and HP for squamous cell carcinoma of the lung (AUC = 0.94, LOOCV = 87%). The best dual combination of biomarkers using LR analysis were found to be AHSG + C3 (AUC = 0.91, LOOCV = 83%) for breast cancer, CLI + HP (AUC = 0.98, LOOCV = 92%) for CRC, C3 + SAA (AUC = 0.97, LOOCV = 91%) for small cell lung carcinoma and HP + SAA for both adenocarcinoma (AUC = 0.98, LOOCV = 96%) and squamous cell carcinoma of the lung (AUC = 0.98, LOOCV = 84%). The high AUC values reported here indicated that these candidate biomarkers have the potential to discriminate accurately between control and cancer groups both individually and in combination with other proteins. Copyright © 2011 UICC.

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The aims of this phase I study were to establish the maximum tolerated dose, safety profile and activity of liposomal daunorubicin, DaunoXome (NeXstar Pharmaceuticals), in the treatment of metastatic breast cancer. DaunoXome was administered intravenously over 2 h in 21 day cycles and doses were increased from 80 to 100, 120 and 150 mg m 2. Sixteen patients were enrolled. A total of 70 cycles of DaunoXome were administered. The maximum tolerated dose was 120 mg m 2, the dose-limiting toxicity being prolonged grade 4 neutropenia or neutropenic pyrexia necessitating dose reductions at 120 and 150 mg m 2. Asymptomatic cardiotoxicity was observed in three patients: grade 1 in one treated with a cumulative dose of 800 mg m 2 and grade 2 in two, one who received a cumulative dose of 960 mg m 2 and the other a cumulative dose of 600 mg m 2 with a previous neoadjuvant doxorubicin chemotherapy of 300 mg m 2. Tumour response was evaluable in 15 patients, of whom two had objective responses, six had stable disease and seven had progressive disease. In conclusion, DaunoXome is associated with mild, manageable toxicities and has anti-tumour activity in metastatic breast cancer. The findings support further phase II evaluation of DaunoXome alone and in combination with other standard non-anthracycline cytotoxic or novel targeted agents. Although the dose-limiting toxicity for DaunoXome was febrile neutropenia at 120 mg m 2, we would recommend this dose for further evaluation, as the febrile neutropenia occurred after four or more cycles in three of the four episodes seen, was short lived and uncomplicated. © 2002 Cancer Research UK.

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Trastuzumab is a humanised monoclonal antibody against the extracellular domain of HER2 (human epidermal growth factor receptor-2) that is overexpressed in about 25% of human breast cancers. It has shown clinical benefit in HER2-positive breast cancer cases when used alone or in combination with chemotherapy. Trastuzumab increases the response rate to chemotherapy and prolongs survival when used in combination with taxanes. In this article, we review the clinical trials where trastuzumab has been administered together with docetaxel, and we present the results of the trastuzumab expanded access programme (EAP) in the UK. Combination of trastuzumab with docetaxel results in similar response rates and time-to-progression with the trastuzumab/paclitaxel combinations. The toxicity of the combination and the risk of heart failure are low. The clinical data for the docetaxel/trastuzumab combination indicate a favourable profile from both the efficacy and the safety point of view and confirm the feasibility and safety of trastuzumab administration both as monotherapy and in combination with docetaxel. © 2004 Blackwell Publishing Ltd.

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Antioestrogens are among the most widely used agents in the treatment of breast cancer. There has been a recent surge of interest in these compounds because of their potential breast cancer chemopreventive properties. The newer generation of antioestrogens, with increased selectivity and better toxicity profiles, have the potential to increase the effectiveness of hormonal treatment of breast cancer. The selective oestrogen receptor modulators (SERMs) hold the promise of revolutionising the care of healthy postmenopausal women with their beneficial effects on bone and lipids in addition to the chemoprevention of breast cancer.