45 research outputs found
Comparative risk-adjusted mortality outcomes after primary surgery, radiotherapy, or androgen-deprivation therapy for localized prostate cancer
Incidence of small lymph node metastases with evidence of extracapsular extension: clinical implications in patients with head and neck squamous cell carcinoma
Small lymph nodes (LN) show evidence of extracapsular extension (ECE) in a significant number of patients. This study was performed to determine the impact of ECE in LN 7 mm as compared with ECE in larger LN
Should phase II cancer screening trials include a control arm? 30th Annual Conference of the International Society for Clinical Biostatistics, August 23-27, 2009, Prague
MET Y1253D-activating point mutation and development of distant metastasis in advanced head and neck cancers
We investigated if the MET-activating point mutation Y1253D influences clinical outcomes in patients with advanced squamous cell carcinoma of the head and neck (HNSCC). The study population consisted of 152 HNSCC patients treated by hyperfractionated radiotherapy alone or concomitant with chemotherapy between September 1994 and July 2000. Tumors were screened for the presence of the MET-activating point mutation Y1253D. Seventy-eight patients (51%) received radiotherapy alone, 74 patients (49%) underwent radiotherapy concomitant with chemotherapy. Median patient age was 54 years and median follow-up was 5.5 years. Distant metastasis-free survival, local relapse-free survival and overall survival were compared with MET Y1253D status. During follow-up, 29 (19%) patients developed distant metastasis. MET Y1253D was detected in tumors of 21 out of 152 patients (14%). Distant metastasis-free survival (P = 0.008) was associated with MET Y1253D. In a multivariate Cox regression model, adjusted for T-category, only presence of MET Y1253D was associated with decreased distant metastasis-free survival: hazard ratio = 2.5 (95% confidence interval: 1.1, 5.8). The observed association between MET Y1253D-activating point mutation and decreased distant metastasis-free survival in advanced HNSCC suggests that MET may be a potential target for specific treatment interventions
Quantitative analysis of extracapsular extension of metastatic lymph nodes and its significance in radiotherapy planning in head and neck squamous cell carcinoma
We performed a histopathologic analysis to assess the extent of the extracapsular extension (ECE) beyond the capsule of metastatic lymph nodes (LN) in head and neck cancer to determine appropriate clinical target volume (CTV) expansions
The Application of Critical Discourse Theory: A Criterion-Referenced Analysis of Reports Relating to Language Revitalisation in Australia and New Zealand
The discipline of language policy and planning (LPP) is often proposed as a viable tool for language revitalisation. However, the conventional paradigm upon which LPP is based is inadequate for such an inherently political, contentious and problematic area of social policy, and does not address the hegemonic and counter-hegemonic discourse that is at the very core of language revitalisation efforts. It is therefore argued here that LPP needs to be explicitly underpinned by critical discourse theory (CDT) if it is to be of genuine use to those involved in language revitalisation efforts, particularly to grass roots language activists. Following an introductory chapter which provides a background to the research and a rationale for it (Chapter 1), there is a critical review of selected literature on LPP and CDT, a review which ends by proposing a list of criteria which, it is argued, can be used to determine the extent to which discourse that is intended to be counter-hegemonic adheres to the principles of effective counter-hegemonic discourse as outlined in the literature on CDT (Chapter 2). In the following three chapters (Chapters 3, 4 & 5), these criteria are applied to the analysis of three recent reports that have a direct bearing on indigenous language revitalisation in Australia (Our Land Our Languages) and New Zealand (Ko Aotearoa Tēnei and Te Reo Mauriora). The first of these reports is found to adhere very closely to the criteria; the second less so; the third almost not at all. The different ways in which each of these reports has been received would tend to support the hypothesis that, other things being equal, the more closely a text of this type conforms to the criteria - that is, the more closely it is aligned to the fundamental principles of effective counter-hegemonic discourse as outlined in CDT - the more likely it is to be positively received and, therefore, to represent an effective challenge to the existing hegemony. The overall conclusion is that CDT can not only assist language activists by providing a basis for determining how successful counter-hegemonic discourse is likely to be in achieving its aims but has the potential to provide LPP with a secure theoretical foundation (Chapter 6)
High Dose-Rate Versus Low Dose-Rate Brachytherapy for Lip Cancer
To analyze the outcome after low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy for lip cancer
Predictors of severe late radiotherapy-related toxicity after hyperfractionated radiotherapy with or without concomitant cisplatin in locally advanced head and neck cancer. Secondary retrospective analysis of a randomized phase III trial (SAKK 10/94)
BACKGROUND AND PURPOSE:
This secondary analysis was performed to identify predictive factors for severe late radiotherapy (RT)-related toxicity after treatment with hyperfractionated RT +/- concomitant cisplatin in locally advanced head and neck cancer.
MATERIALS AND METHODS:
Patients were retrospectively analyzed from the previously reported randomized phase III trial: SAKK 10/94. Severe late RT-related toxicity was defined as late RTOG ⩾ grade 3 toxicity starting 3months after end of RT and/or potential treatment-related death within 3years of randomization.
RESULTS:
Two hundred and thirteen randomized patients were analyzed; 84 (39%) experienced severe late RT-related toxicity. With median follow-up of 9.7years (range, 0.4-15.4years), median time to severe late RT-related toxicity was 9.6years. In the univariate Cox proportional hazards model the following variables were associated with severe late RT-related toxicity: advanced N-classification (p<0.001); technically unresectable disease (p=0.04); weight loss ratio (p=0.003); supportive measures (p=0.009) and severe acute dysphagia (p=0.001). In the subsequent multivariate analysis all variables except use of supportive measures remained statistically significant.
CONCLUSIONS:
Chemotherapy did not appear to affect severe late RT-related toxicity, but advanced N-classification, technically unresectable disease, weight loss ratio, and severe acute dysphagia were independent predictive factors for severe late RT-related toxicity
Optical monitoring of surface processes relevant to thin film growth by chemical vapour deposition
This thesis reports on the investigation of the use of reflectance anisotropy spectroscopy (RAS) as an in-situ monitor for the preparation and oxidation of GaAs(100) c(4x4) surfaces using a CVD 2000 MOCVD reactor. These surfaces were oxidised using air. It was found that it was possible to follow surface degradation using RA transients at 2.6eV and 4eV. From this data it was possible to speculate on the nature of the surface oxidation process. A study was performed into the rate of surface degradation under different concentrations of air, it was found that the relation between the air concentration and the surface degradation was complicated but that the behaviour of the first third of the degradation approximated a first order behaviour. An estimation of the activation energy of the process was then made, and an assessment of the potential use of the glove-box for STM studies which is an integral part of the MOCVD equipment was also made. Following this, a description is given of the construction of an interferometer for monitoring thin film growth. An investigation is also described into two techniques designed to evaluate the changes in reflected intensity as measured by an interferometer. The first technique uses an iteration procedure to determine the film thickness from the reflection data. This is done using a Taylor series expansion of the thin film reflection function to iterate for the thickness. Problems were found with the iteration when applied to noisy data, these were solved by using a least squares fit to smooth the data. Problems were also found with the iteration at the turning points these were solved using the derivative of the function and by anticipating the position of the turning points. The second procedure uses the virtual interface method to determine the optical constants of the topmost deposited material, the virtual substrate, and the growth rate. This method is applied by using a Taylor series expansion of the thin film reflection function for each of the variables, this is then fitted to the data like a least squares fit. The fit parameters are then used to modify the constants, this process is the repeated to iterate for the actual values. These procedures are tested on simulated data with simulated noise based on the standard distribution curve. These routines were implemented using Visual Basic and C++. (author)SIGLEAvailable from British Library Document Supply Centre- DSC:DXN056386 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
