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The long-term outcome of treated high-risk nonmuscle-invasive bladder cancer
This article is available open access through the publisher’s website from the link below. Copyright © 2012 American Cancer Society.BACKGROUND: The treatment of high-risk nonmuscle-invasive bladder cancer (NMIBC) is difficult given its unpredictable natural history and patient comorbidities. Because current case series are mostly limited in size, the authors report the outcomes from a large, single-center series.
METHODS: The authors reviewed all patients with primary, high-risk NMIBC at their institution from 1994 to 2010. Outcomes were matched with clinicopathologic data. Patients who had muscle invasion within 6 months or had insufficient follow-up (<6 months) were excluded. Correlations were analyzed using multivariable Cox regression and log-rank analysis (2-sided; P < .05).
RESULTS: In total, 712 patients (median age, 73.7 years) were included. Progression to muscle invasion occurred in 110 patients (15.8%; 95% confidence interval [CI], 13%-18.3%) at a median of 17.2 months (interquartile range, 8.9-35.8 months), including 26.5% (95% CI, 22.2%-31.3%) of the 366 patients who had >5 years follow-up. Progression was associated with age (hazard ratio [HR], 1.04; P = .007), dysplastic urothelium (HR, 1.6; P = .003), urothelial cell carcinoma variants (HR, 3.2; P = .001), and recurrence (HR, 18.3; P .6).
CONCLUSIONS: Within a program of conservative treatment, progression of high-risk NMIBC was associated with a poor prognosis. Surveillance and bacillus Calmette-Guerin were ineffective in altering the natural history of this disease. The authors concluded that the time has come to rethink the paradigm of management of this disease.GlaxoSmithKline, Yorkshire Cancer Research, Sheffield Hospitals Charitable Trust, Astellas Educational Foundation, and the European Union
Reduction and approximation in gyrokinetics
The gyrokinetics formulation of plasmas in strong magnetic fields aims at the
elimination of the angle associated with the Larmor rotation of charged
particles around the magnetic field lines. In a perturbative treatment or as a
time-averaging procedure, gyrokinetics is in general an approximation to the
true dynamics. Here we discuss the conditions under which gyrokinetics is
either an approximation or an exact operation in the framework of reduction of
dynamical systems with symmetryComment: 15 pages late
Drift-Ordered Fluid Equations for Field-Aligned Modes in Low-β Collisional Plasma with Equilibrium Pressure Pedestals
Heat and momentum transport in arbitrary mean-free path plasma with a Maxwellian lowest order distribution function
A New, Explicitly Collisional Contribution to the Gyroviscosity and the Radial Electric Field in a Collisional Tokamak
Comparison of neoclassical predictions with measured flows and evaluation of a poloidal impurity density asymmetry
The HBI in a quasi-global model of the intracluster medium
In this paper we investigate how convective instabilities influence heat
conduction in the intracluster medium (ICM) of cool-core galaxy clusters. The
ICM is a high-beta, weakly collisional plasma in which the transport of
momentum and heat is aligned with the magnetic field. The anisotropy of heat
conduction, in particular, gives rise to instabilities that can access energy
stored in a temperature gradient of either sign. We focus on the heat-flux
buoyancy-driven instability (HBI), which feeds on the outwardly increasing
temperature profile of cluster cool cores. Our aim is to elucidate how the
global structure of a cluster impacts on the growth and morphology of the
linear HBI modes when in the presence of Braginskii viscosity, and ultimately
on the ability of the HBI to thermally insulate cores. We employ an idealised
quasi-global model, the plane-parallel atmosphere, which captures the essential
physics -- e.g. the global radial profile of the cluster -- while letting the
problem remain analytically tractable. Our main result is that the dominant HBI
modes are localised to the the innermost (~<20%) regions of cool cores. It is
then probable that, in the nonlinear regime, appreciable field-line insulation
will be similarly localised. Thus, while radio-mode feedback appears necessary
in the central few tens of kpc, heat conduction may be capable of offsetting
radiative losses throughout most of a cool core over a significant fraction of
the Hubble time. Finally, our linear solutions provide a convenient numerical
test for the nonlinear codes that tackle the saturation of such convective
instabilities in the presence of anisotropic transport.Comment: MNRAS, in press; minor modifications from v
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