Abstract
10% of all pediatric brain tumors arise in the brainstem. Amongst these gliomas are the most common while other entities are rare and infrequently described in the literature. In this study ...we investigated the prevalence of non-gliomatous tumors in the brainstem. Amongst the 1323 embryonal tumours received at the RBTC, we identified 17 cases of ETMRs (17/165) that presented as brainstem primaries. Previously grouped within CNS-PNETs, ETMR, is a new WHO diagnostic entity, characterized by C19MC alterations. ETMR is a disease of infancy, the clinical spectrum of which is poorly understood. ETMRs arise at multiple CNS locations including cerebrum being most common (60%,) followed by cerebellum (18%) and midline structures (6%); notably 10% were brainstem primaries, mimicking DIPG radiologically. All patients presented with a short history of progressive neurological symptoms, with most common signs and symptoms of cranial neuropathies, long tract signs and gait disturbance. Median age at diagnosis was 27 months (range 16-75months) with a male to female ratio of 0.9:1. Predominantly localized (M0-94%, M2-3 -6%) majority of patients underwent upfront biopsy or partial resection (15/17:88%), while complete tumor resection was achieved in 2 cases. All patients received heterogenous combination of chemotherapy with and without radiotherapy. Majority of patients progressed rapidly with median time to progression of 4 months and overall survival of < 13 months. The only long-term surviving patient had complete resection dose intensified chemotherapy and radiation (OS 202months). Primary ETMRs in the brainstem are under recognised entities and carry a dismal prognosis. Although rapidly progressive, prompt recognition, maximal resection and management with multimodal adjuvant therapy should be considered in cases with brainstem disease.
We consider the case of a $\sqrt{\mathrm{SWAP}}$ quantum gate and its
optimized entangling action, via continuous dynamical decoupling, in the
presence of dephasing noise. We illustrate the procedure ...in the specific case
where only the two-qubit operation is controlled and no single-qubit operations
are included in the description. To compare the optimized dynamics in the
presence of noise with the ideal case, we use the standard fidelity measure.
Then we discuss the importance of using optimized gates in the quantum
operational-probabilistic theory. Because of their importance for the explicit
construction of the completely positive maps representing the operations, we
derive optimized Kraus operators in this specific case, focusing on the
entanglement operation. We then show how to visualize the time evolution of
each Kraus operator as a curve in a three-dimensional Euclidean space. Finally,
we connect this formalism with the operational framework of quantum mechanics
by describing a possible set of measurements that could be performed to obtain
the Kraus operators.
We have used the MOST (Microvariability and Oscillations of STars) microsatellite to obtain four weeks of contiguous high-precision broadband visual photometry of the O7.5III(n)((f)) star {\xi} ...Persei in November 2011. This star is well known from previous work to show prominent DACs (Discrete Absorption Components) on time-scales of about 2 d from UV spectroscopy and NRP (Non Radial Pulsation) with one (l = 3) p-mode oscillation with a period of 3.5 h from optical spectroscopy. Our MOST-orbit (101.4 min) binned photometry fails to reveal any periodic light variations above the 0.1 mmag 3-sigma noise level for periods of hours, while several prominent Fourier peaks emerge at the 1 mmag level in the two-day period range. These longer-period variations are unlikely due to pulsations, including gravity modes. From our simulations based upon a simple spot model, we deduce that we are seeing the photometric modulation of several co-rotating bright spots on the stellar surface. In our model, the starting times (random) and lifetimes (up to several rotations) vary from one spot to another yet all spots rotate at the same period of 4.18 d, the best-estimated rotation period of the star. This is the first convincing reported case of co-rotating bright spots on an O star, with important implications for drivers of the DACs (resulting from CIRs - Corotating Interaction Regions) with possible bright-spot generation via a breakout at the surface of a global magnetic field generated by a subsurface convection zone.
Introduction
Very rare pediatric tumors (VRTs), defined by an annual incidence ≤2 per million inhabitants, represent a heterogeneous group of cancers. Due to their extremely low incidence, knowledge ...on these tumors is scant. Since 2012, the French Very Rare Tumors Committee (FRACTURE) database has recorded clinical data about VRTs in France. This study aims: (a) to describe the tumors registered in the FRACTURE database; and (b) to compare these data with those registered in the French National Registry of Childhood Cancer (RNCE).
Methods
Data recorded in the FRACTURE database between January 1, 2012 and December 31, 2018 were analyzed. In addition, these data were compared with those of the RNCE database between 2012 and 2015 to evaluate the completeness of the documentation and understand any discrepancies.
Results
A total of 477 patients with VRTs were registered in the FRACTURE database, representing 97 histological types. Of the 14 most common tumors registered in the RNCE (772 patients), only 19% were also registered in the FRACTURE database. Total 39% of children and adolescent VRTs registered in the RNCE and/or FRACTURE database (323 of a total of 828 patients) were not treated in or linked to a specialized pediatric oncology unit.
Conclusion
VRTs represent many different heterogenous entities, which nevertheless account for 10% of all pediatric cancers diagnosed each year. Sustainability in the collection of these rare tumor cases is therefore important, and a regular systematic collaboration between the FRACTURE database and the RNCE register helps to provide a more exhaustive picture of these VRTs and allow research completeness for some peculiar groups of patients.
Purposes
The purpose of this study was to retrospectively study embryonal tumors with multilayered rosettes (ETMR), a rare new entity that gathers ETAN-TR (embryonal tumor with abundant neuropil and ...true rosettes), ependymoblastomas, and medulloepitheliomas, in order to improve their descriptions and try to better define therapeutic modalities.
Methods
Patients with ETMR, ETAN-TR, ependymoblastoma, and medulloepithelioma treated in SFCE centres (Société Française de lutte contre les Cancers et les leucémies de l'Enfant et de l'adolescent) since 2000 were collected. Data were retrieved from clinical charts.
Results
Thirty-eight patients were included in the analysis. Seventeen had an ETAN-TR, 13 had a medulloepithelioma, and 8 had an ETMR. No ependymoblastoma was included. The median age at diagnosis was 31 months (range, 2.8–141 months). The predominant tumor location was supratentorial (66 %); 18.4 % patients had metastatic lesion.
LIN28A expression was positive in 11/11 patients. Amplification of the locus 19q13.42 was positive in 10/12 patients. Thirty patients were treated according to the primitive neuroectodermal tumors of high risk (PNET-HR) protocol. The median time of follow-up was 0.9 years (range 0.1 to 15.3 years). The 1-year event-free survival (EFS) and overall survival (OS) were, respectively, 36 % CI 95 % (23–55) and 45 % CI 95 % (31–64). On multivariate analysis, complete surgical resection, radiotherapy, and high-dose chemotherapy were associated with a better overall survival with a relative risk of, respectively, 7.9 CI 95 % (2.6–23.5)
p
< 0.0002, 41.8 CI 95 % (9.4–186)
p
< 0.0001, and 3.5 CI 95 % (1.3–9.5)
p
= 0.012.
Conclusion
Prognosis of ETMR remains dismal despite multimodal therapy. LIN28A immunostaining and 19q13.42 amplification should be systematically done to secure the diagnosis. Complete surgical resection, radiotherapy, and high-dose chemotherapy are associated with better outcome.
Maintenance chemotherapy is an important part of the treatment of ALL in children. It relies on the long-term oral administration of daily low-dose mercaptopurin and weekly low-dose methotrexate. ...Although it has been used in the clinic for decades, its mechanisms of action remain unclear. Here, we investigated different angiogenic and immune biomarkers to gain insights into the mechanisms of action of maintenance therapy in children with ALL. We thus monitored circulating endothelial cells (CEC), endothelial progenitor cells (EPC) and endothelial microparticles (EMP), pro-angiogenic factors (VEGF, VEGFR-1 and Ang-2), anti-angiogenic factor thrombospondin-1 (THBS1) and regulatory T lymphocytes (Treg) in 47 children with ALL during the maintenance phase of their treatment (at treatment initiation and after 6, 12 and 18 months). We observed a statistically significant decrease in EPC and EMP counts throughout the maintenance phase associated with a significant increase in THBS1 levels. No significant change was detected in other angiogenic markers or in Treg numbers.The results presented here indicate that maintenance therapy in children with ALL exerts its antitumor activity at least in part through anti-angiogenic effects, similar to those induced by metronomic chemotherapy. Larger studies are now warranted to validate these findings and determine their clinical implications.
Abstract
PURPOSE
To assess the 3-year EFS rate of children younger than 5 years of age with high-risk medulloblastoma (MB) treated according to the prospective multicenter trial HR MB-5.
PATIENTS AND ...METHODS
After surgery, all children received 2 cycles of Etoposide- Carboplatine. If partial (PR) or complete response (CR) was achieved after induction chemotherapy, children received 2 courses of thiotepa (600mg/m²) with stem cell rescue. For patients in CR after high-dose chemotherapy, they received one course of Cyclophosphamide – Busilvex with stem cell rescue (Phase I part). The others patients (not in PR after induction or in CR after thiotepa) were treated with 2 cycles of Temozolomide-Irinotecan followed by age-adapted craniospinal irradiation and maintenance treatment.
RESULTS
28 children (2 to 4 years; median: 3.0 years) were enrolled. Group 3 MB were most common (57%). The response rate to Etoposide-Carboplatine was 60.7%. Among 20 patients treated with Thiotepa, 13 children were in CR and received Cyclophosphamide – Busilvex without radiotherapy. Out of them, 9 patients (45%) are alive in CR without craniospinal irradiation (median follow-up 5 years). Among 15 patients treated with radiotherapy, 8 patients are alive (median follow-up 3.8 years). The study was prematurely stopped for an excess of events. The median follow-up was 4 years (range 1.5 - 6.1). The 3-year EFS and OS were 42.3% 25.9 - 60.6 and 71.3% 52.7 - 84.7, respectively.
CONCLUSIONS
This risk-adapted strategy did not improve EFS in young children with high-risk MB. However, the study shows that good responders to chemotherapy can be cured without recourse to irradiation.
We report the serendipitous discovery of a collision ring galaxy, identified as 2MASX J06470249+4554022, which we have dubbed 'Auriga's Wheel', found in a SUPRIME-CAM frame as part of a larger Milky ...Way survey. This peculiar class of galaxies is the result of a near head-on collision between typically, a late type and an early type galaxy. Subsequent GMOS-N long-slit spectroscopy has confirmed both the relative proximity of the components of this interacting pair and shown it to have a redshift of 0.111. Analysis of the spectroscopy reveals that the late type galaxy is a LINER class Active Galactic Nuclei while the early type galaxy is also potentially an AGN candidate, this is very uncommon amongst known collision ring galaxies. Preliminary modeling of the ring finds an expansion velocity of ~200 kms^-1 consistent with our observations, making the collision about 50 Myr old. The ring currently has a radius of about 10 kpc and a bridge of stars and gas is also visible connecting the two galaxies.
The Moon is an archetypal atmosphere-less celestial body in the Solar System. For such bodies, the environments are characterized by complex interaction among the space plasma, tenuous neutral gas, ...dust and the outermost layer of the surface. Here we propose the SELMA mission (Surface, Environment, and Lunar Magnetic Anomalies) to study how airless bodies interact with space environment. SELMA uses a unique combination of remote sensing via ultraviolet and infrared wavelengths, and energetic neutral atom imaging, as well as in situ measurements of exospheric gas, plasma, and dust at the Moon. After observations in a lunar orbit for one year, SELMA will conduct an impact experiment to investigate volatile content in the soil of the permanently shadowed area of the Shackleton crater. SELMA also carries an impact probe to sound the Reiner-Gamma mini-magnetosphere and its interaction with the lunar regolith from the SELMA orbit down to the surface. SELMA was proposed to the European Space Agency as a medium-class mission (M5) in October 2016. Research on the SELMA scientific themes is of importance for fundamental planetary sciences and for our general understanding of how the Solar System works. In addition, SELMA outcomes will contribute to future lunar explorations through qualitative characterization of the lunar environment and, in particular, investigation of the presence of water in the lunar soil, as a valuable resource to harvest from the lunar regolith.
•We propose SELMA mission to study how airless bodies interact with space environment.•SELMA uses a unique combination of remote sensing and in situ measurements at Moon.•SELMA investigates the interaction between the plasma, gas, dust and surface at Moon.•SELMA conducts two impact campaign measurements to study the environment.•SELMA aims to launch in 2029 as a medium class mission of ESA's Cosmic Vision program.
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