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Phase I study of dose escalation to dominant intraprostatic lesions using high-dose-rate brachytherapy.
PurposeRadiation dose escalation for prostate cancer improves biochemical control but is limited by toxicity. Magnetic resonance spectroscopic imaging (MRSI) can define dominant intraprostatic lesions (DIL). This phase I study evaluated dose escalation to MRSI-defined DIL using high-dose-rate (HDR) brachytherapy.Material and methodsEnrollment was closed early due to low accrual. Ten patients with prostate cancer (T2a-3b, Gleason 6-9, PSA < 20) underwent pre-treatment MRSI, and eight patients had one to three DIL identified. The eight enrolled patients received external beam radiation therapy to 45 Gy and HDR brachytherapy boost to the prostate of 19 Gy in 2 fractions. MRSI images were registered to planning CT images and DIL dose-escalated up to 150% of prescription dose while maintaining normal tissue constraints. The primary endpoint was genitourinary (GU) toxicity.ResultsThe median total DIL volume was 1.31 ml (range, 0.67-6.33 ml). Median DIL boost was 130% of prescription dose (range, 110-150%). Median urethra V120 was 0.15 ml (range, 0-0.4 ml) and median rectum V75 was 0.74 ml (range, 0.1-1.0 ml). Three patients had acute grade 2 GU toxicity, and two patients had late grade 2 GU toxicity. No patients had grade 2 or higher gastrointestinal toxicity, and no grade 3 or higher toxicities were noted. There were no biochemical failures with median follow-up of 4.9 years (range, 2-8.5 years).ConclusionsDose escalation to MRSI-defined DIL is feasible. Toxicity was low but incompletely assessed due to limited patients' enrollment
Percutaneous Liver Biopsy after Living Donor Liver Transplantation Resulting in Fulminant Hepatic Failure: The First Reported Case of Hepatic Compartment Syndrome
A 28-year-old female who underwent live donor liver transplantation 3 years prior presented after percutaneous liver biopsy with abdominal and shoulder pain, nausea, vomiting, and elevated liver enzymes. Computed tomography (CT) showed an intrahepatic and subcapsular hematoma. There was a progressive increase in liver enzymes, bilirubin, and INR and a decline in hemoglobin. Subsequent CT imaging revealed flattening of the portal vein consistent with compression by the enlarging hematoma. Liver failure ensued and the patient required urgent retransplantation. The explant demonstrated ischemic necrosis of greater than 90% of the liver parenchyma. We report this case of âHepatic Compartment Syndromeâ leading to fulminant hepatic failure
Resonant and Non-Resonant Effects in Photon-Technipion Production at Lepton Colliders
Lepton collider experiments can search for light technipions in final states
made striking by the presence of an energetic photon: e+e- \to
\photon\technipion. To date, searches have focused on either production
through anomalous coupling of the technipions to electroweak gauge bosons or on
production through a technivector meson (\technirho, \techniomega) resonance.
This paper creates a combined framework in which both contributions are
included. This will allow stronger and more accurate limits on technipion
production to be set using existing data from LEP or future data from a
higher-energy linear collider. We provide explicit formulas and sample
calculations (analytic and Pythia) in the framework of the Technicolor Straw
Man Model, a model that includes light technihadrons.Comment: 11 pages, including title page, 3 figures; version 2: references
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GALICS III: Predicted properties for Lyman Break Galaxies at redshift 3
This paper illustrates how mock observational samples of high-redshift
galaxies with sophisticated selection criteria can be extracted from the
predictions of GALICS, a hybrid model of hierarchical galaxy formation that
couples the outputs of large cosmological simulations and semi-analytic recipes
to describe dark matter collapse and the physics of baryons respectively. As an
example of this method, we focus on the properties of Lyman Break Galaxies at
redshift 3. With the MOMAF software package described in a companion paper, we
generate a mock observational sample with selection criteria as similar as
possible to those implied in the actual observations of z = 3 LBGs by Steidel
et al.(1995). Our model predictions are in good agreement with the observed
number density and 2D correlation function. We investigate the optical/IR
luminosity budget as well as several other physical properties of LBGs and find
them to be in general agreement with observed values. Looking into the future
of these LBGs we predict that 75% of them end up as massive ellipticals today,
even though only 35% of all our local ellipticals are predicted to have a LBG
progenitor. In spite of some shortcomings, this new 'mock observation' method
clearly represents a necessary first step toward a more accurate comparison
between hierarchical models of galaxy formation and real observational surveys.Comment: 19 pages, 15 figures, submitted to MNRAS. Full resolution figures at
http://galics.iap.fr
Clinical outcome and prognostic factors for central neurocytoma: twenty year institutional experience
Central neurocytomas are uncommon intraventricular neoplasms whose optimal management remains controversial due to their rarity. We assessed outcomes for a historical cohort of neurocytoma patients and evaluated effects of tumor atypia, size, resection extent, and adjuvant radiotherapy. Progression-free survival (PFS) was measured by Kaplan-Meier and Cox proportional hazards methods. A total of 28 patients (15 males, 13 females) were treated between 1995 and 2014, with a median age at diagnosis of 26 years (range 5-61). Median follow-up was 62.2 months and 3 patients were lost to follow-up postoperatively. Thirteen patients experienced recurrent/progressive disease and 2-year PFS was 75% (95% CI 53-88%). Two-year PFS was 48% for MIB-1 labeling >4% versus 90% for â€4% (HR 5.4, CI 2.2-27.8, p = 0.0026). Nine patients (32%) had gross total resections (GTR) and 19 (68%) had subtotal resections (STR). PFS for >80% resection was 83 versus 67% for â€80% resection (HR 0.67, CI 0.23-2.0, p = 0.47). Three STR patients (16%) received adjuvant radiation which significantly improved overall PFS (p = 0.049). Estimated 5-year PFS was 67% for STR with radiotherapy versus 53% for STR without radiotherapy. Salvage therapy regimens were diverse and resulted in stable disease for 54% of patients and additional progression for 38 %. Two patients with neuropathology-confirmed atypical neurocytomas died at 4.3 and 113.4 months after initial surgery. For central neurocytomas, MIB-1 labeling index >4% is predictive of poorer outcome and our data suggest that adjuvant radiotherapy after STR may improve PFS. Most patients requiring salvage therapy will be stabilized and multiple modalities can be effectively utilized
The chemical characterisation of halo substructure in the Milky Way based on APOGEE
Galactic haloes in a -Cold Dark Matter (CDM) universe are
predicted to host today a swarm of debris resulting from cannibalised dwarf
galaxies that have been accreted via the process of hierarchical mass assembly.
The chemo-dynamical information recorded in the Galactic stellar populations
associated with such systems helps elucidate their nature, placing constraints
on the mass assembly history of the Milky Way. Using data from the APOGEE and
\textit{Gaia} surveys, we examine APOGEE targets belonging to the following
substructures in the stellar halo: Heracles, \textit{Gaia}-Enceladus/Sausage
(GES), Sagittarius dSph, the Helmi stream, Sequoia, Thamnos, Aleph, LMS-1,
Arjuna, I'itoi, Nyx, Icarus, and Pontus. We examine the distributions of all
substructures in chemical space, considering the abundances of elements
sampling various nucleosynthetic pathways. Our main findings include: {\it i)}
the chemical properties of GES, Heracles, the Helmi stream, Sequoia, Thamnos,
LMS-1, Arjuna, and I'itoi match qualitatively those of dwarf satellites of the
Milky Way, such as the Sagittarius dSph; {\it ii)} the abundance pattern of the
recently discovered inner Galaxy substructure Heracles differs statistically
from that of populations formed {\it in situ}. Heracles also differs chemically
from all other substructures; {\it iii)} the abundance patterns of Sequoia
(selected in various ways), Arjuna, LMS-1, and I'itoi are indistinguishable
from that of GES, indicating a possible common origin; {\it iv)} the abundance
patterns of the Helmi stream and Thamnos substructures are different from all
other halo substructures; {\it v)} the chemical properties of Nyx and Aleph are
very similar to those of disc stars, implying that these substructures likely
have an \textit{in situ} origin.Comment: Submitted to MNRAS. 39 page
A Multidisciplinary Investigation of a Polycythemia Vera Cancer Cluster of Unknown Origin
Cancer cluster investigations rarely receive significant public health resource allocations due to numerous inherent challenges and the limited success of past efforts. In 2008, a cluster of polycythemia vera, a rare blood cancer with unknown etiology, was identified in northeast Pennsylvania. A multidisciplinary group of federal and state agencies, academic institutions, and local healthcare providers subsequently developed a multifaceted research portfolio designed to better understand the cause of the cluster. This research agenda represents a unique and important opportunity to demonstrate that cancer cluster investigations can produce desirable public health and scientific outcomes when necessary resources are available
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