1,198 research outputs found
Do cancer detection rates differ between transperineal and transrectal micro-ultrasound mpMRI-fusion-targeted prostate biopsies? A propensity score-matched study
Introduction: High-resolution micro-ultrasound (micro-US) is a novel precise imaging modality that allows targeted prostate biopsies and multiparametric magnet resonance imaging (mpMRI) fusion. Its high resolution relying on a 29 MHz transducer allows real-time visualisation of prostate cancer lesions; this might overcome the inaccuracy of conventional MRI-US fusion biopsy strategies. We compared cancer detection rates in patients who underwent transrectal (TR-B) versus transperineal (TP-B) MR-micro-US fusion biopsy. Materials and methods: 1:2 propensity score matching was performed in 322 consecutive procedures: 56 TR-B and 266 TP-B. All prostate biopsies were performed using ExactVuTM micro-US system with mpMRI image fusion. Clinically significant disease was defined as grade group ≥2. The primary objective was to evaluate the detection of clinically significant disease according to access route. The secondary outcomes were to compare the respective detection rates of random and targeted biopsies stratified per access route and to evaluate micro-US for its potential added value. Results: 47 men undergoing TR-B and 88 undergoing TP-B were matched for age, PSA, clinical stage, prostate volume, PIRADS score, number of mpMRI-visible lesions and indication to biopsy. The detection rates of clinically significant and of any prostate cancer did not differ between the two groups (45% TR-B vs 42% TP-B; p = 0.8, and 57% TR-B vs 59% TP-B; p = 0.9, respectively). Detection rates also did not differ significantly between random (p = 0.4) and targeted biopsies (p = 0.7) stratified per access route. Micro-US targeted biopsy detected 36 MRI-invisible lesions in 33 patients; 19% of these lesions were positive for clinically significant disease. Overall, micro-US targeted biopsies upgraded 2% of patients to clinically significant disease that would have been missed otherwise. Conclusions: MR-micro-US-fusion TR-B and TP-B have similar diagnostic yields in terms of detection rates of clinically significant prostate cancer. Micro-US targeted biopsy appears to have an additional diagnostic value over systematic and MRI-targeted biopsies
Deviations from the Gaussian distribution of mesoscopic conductance fluctuations
The conductance distribution of metallic mesoscopic systems is considered.
The variance of this distribution describes the universal conductance
fluctuations, yielding a Gaussian distribution of the conductance. We calculate
diagrammatically the third cumulant of this distribution, the leading deviation
from the Gaussian. We confirm random matrix theory calculations that the
leading contribution in quasi-one dimension vanishes. However, in quasi two
dimensions the third cumulant is negative, whereas in three dimensions it is
positive.Comment: 9 pages, Revtex, with eps figures,to appear in Phys Rev
Anomalous Conductance Distribution in Quasi-One Dimension: Possible Violation of One-Parameter Scaling Hypothesis
We report measurements of conductance distribution in a set of
quasi-one-dimensional gold wires. The distribution includes the second cumulant
or the variance which describes the universal conductance fluctuations, and the
third cumulant which denotes the leading deviation. We have observed an
asymmetric contribution--or, a nonvanishing third cumulant--contrary to the
expectation for quasi-one-dimensional systems in the noninteracting theories in
the one-parameter scaling framework, which include the perturbative
diagrammatic calculations and the random matrix theory.Comment: 5 PAGE
Talented in dance: The Bloom Stage Model revisited in the personal histories of dance students
"Optical conductance fluctuations: diagrammatic analysis in Landauer approach and non-universal effects"
The optical conductance of a multiple scattering medium is the total
transmitted light of a diffuse incoming beam. This quantity, very analogous to
the electronic conductance, exhibits universal conductance fluctuations. We
perform a detailed diagrammatic analysis of these fluctuations. With a
Kadanoff-Baym technique all the leading diagrams are systematically generated.
A cancellation of the short distance divergencies occurs, that yields a well
behaved theory. The analytical form of the fluctuations is calculated and
applied to optical systems. Absorption and internal reflections reduce the
fluctuations significantly.Comment: 25 pages Revtex 3.0, 18 seperate postscript figure
Intensity Distribution of Waves Transmitted Through a Multiple Scattering Medium
The distributions of the angular transmission coefficient and of the total
transmission are calculated for multiple scattered waves. The calculation is
based on a mapping to the distribution of eigenvalues of the transmission
matrix. The distributions depend on the profile of the incoming beam. The
distribution function of the angular transmission has a stretched exponential
decay. The total-transmission distribution grows log-normally whereas it decays
exponentially.Comment: 8 pages, revtex3.0, 3 postscript figures, NvR0
Field and intensity correlations in random media
Measurements of the microwave field transmitted through a random medium
allows direct access to the field correlation function, whose complex square is
the short range or C1 contribution to the intensity correlation function C. The
frequency and spatial correlation function are compared to their Fourier pairs,
the time of flight distribution and the specific intensity, respectively. The
longer range contribution to intensity correlation is obtained directly by
subtracting C1 from C and is in good agreement with theory.Comment: 9 pages, 5 figures, submitted to Phys.Rev.
Incidence and survival of patients with oligometastatic esophagogastric cancer: A multicenter cohort study
urpose/objective: This multicenter study assessed the incidence and survival of patients with esophagogastric cancer and oligometastatic disease (OMD) in two tertiary referral cancer centers in The Netherlands and Switzerland.
Materials/methods: Between 2010 and 2021, patients with metastatic esophagogastric cancer were identified. Patients with de-novo OMD were included (first-time diagnosis of ≤5 distant metastases on 18F-FDG-PET/CT). Control of the primary tumor was considered in patients who underwent primary tumor resection or definitive chemoradiotherapy without locoregional recurrence. Treatment of OMD was categorized into (1) systemic therapy, (2) local treatment (stereotactic body radiotherapy or metastasectomy), (3) local plus systemic therapy, or (4) best supportive care. The primary outcomes were overall survival (OS) and independent prognostic factors for OS. Independent prognostic factors for OS were analyzed using multivariable Cox proportional hazard models.
Results: In total, 830 patients with metastatic esophagogastric cancer were identified of whom 200 patients with de-novo OMD were included (24%). The majority of included patients had esophageal cancer (73%) with adenocarcinoma histology (79%) and metachronous OMD (52%). The primary tumor was controlled in 68%. Treatment of OMD was systemic therapy (25%), local treatment (43%), local plus systemic therapy (13%), or best supportive care (18%). Median follow-up was 14 months (interquartile range: 7-27). Median OS was 16 months (95% CI: 13-21). Improved OS was independently associated with local plus systemic therapy compared with systemic therapy alone (hazard ratio [HR] 0.47, 95% confidence interval [CI]: 0.25-0.87). Worse OS was independently associated with squamous cell carcinoma (HR 1.70, 95% CI: 1.07-2.74), bone oligometastases (HR 2.44, 95% CI: 1.28-4.68), brain oligometastases (HR 1.98, 95% CI: 1.05-4.69), and two metastatic locations (HR 2.07, 95% CI: 1.04-4.12). Median OS after local plus systemic therapy was 35 months (95% CI: 22-NA) as compared with 13 months (95% CI: 9-21, p < 0.001) after systemic therapy alone for OMD.
Conclusion: Patients with metastatic esophagogastric cancer present in 25% with de-novo OMD. Local treatment of OMD plus systemic therapy was independently associated with long-term OS and independently improved OS when compared with systemic therapy alone. Randomized controlled trials are warranted to confirm these results.
Keywords: Esophageal neoplasms; Gastric neoplasms; Lymphatic metastasis; Metastasectomy; Neoplasm metastasis; Radiosurgery
Spatial field correlation, the building block of mesoscopic fluctuations
The absence of self averaging in mesoscopic systems is a consequence of
long-range intensity correlation. Microwave measurements suggest and
diagrammatic calculations confirm that the correlation function of the
normalized intensity with displacement of the source and detector,
and , respectively, can be expressed as the sum of three terms, with
distinctive spatial dependences. Each term involves only the sum or the product
of the square of the field correlation function, . The
leading-order term is the product, the next term is proportional to the sum.
The third term is proportional to .Comment: Submitted to PR
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