Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions

OBJECTIVE: Low-dose-rate brachytherapy (LDR-BT) in localized prostate cancer is available since 15 years in Italy. We realized the first national multicentre and multidisciplinary data collection to evaluate LDR-BT practice, given as monotherapy, and outcome in terms of biochemical failure. METHODS: Between May 1998 and December 2011, 2237 patients with early-stage prostate cancer from 11 Italian community and academic hospitals were treated with iodine-125 ((125)I) or palladium-103 LDR-BT as monotherapy and followed up for at least 2 years. (125)I seeds were implanted in 97.7% of the patients: the mean dose received by 90% of target volume was 145 Gy; the mean target volume receiving 100% of prescribed dose (V100) was 91.1%. Biochemical failure-free survival (BFFS), disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan-Meier method. Log-rank test and multivariable Cox regression were used to evaluate the relationship of covariates with outcomes. RESULTS: Median follow-up time was 65 months. 5- and 7-year DSS, OS and BFFS were 99 and 98%, 94 and 89%, and 92 and 88%, respectively. At multivariate analysis, the National Comprehensive Cancer Network score (p < 0.0001) and V100 (p = 0.09) were correlated with BFFS, with V100 effect significantly different between patients at low risk and those at intermediate/high risk (p = 0.04). Short follow-up and lack of toxicity data represent the main limitations for a global evaluation of LDR-BT. CONCLUSION: This first multicentre Italian report confirms LDR-BT as an excellent curative modality for low-/intermediate-risk prostate cancer. ADVANCES IN KNOWLEDGE: Multidisciplinary teams may help to select adequately patients to be treated with brachytherapy, with a direct impact on the implant quality and, possibly, on outcome

Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity &gt; 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

A Fast 650V Chopper Driver

In the framework of Linac4 and the Superconducting Proton Linac (SPL) studies at CERN, the design for a beam chopper has been carried out . This paper describes a new chopper driver amplifier providing 650 V on 50 Ω with fronts of about 2 ns and a repetition frequency of up to 45 MHz

Development of radiation-hard solid-state amplifiers for kilo-gray environments using COTS components

The high-luminosity Large Hadron Collider (LHC) (HL-LHC) project is the upgrade of the LHC to increase its luminosity by a factor of 5 compared with the nominal value. The LHC injector upgrade (LIU) project aims at upgrading the LHC injector chain to reach the goal of the HL-LHC. The LIU project covers all injectors, that is, the Linac 4, proton synchrotron (PS) booster (PSB), PS, and super PS (SPS). In the PSB, the present ferrite-loaded RF accelerating systems will be replaced with magnetic alloy (Finemet)-loaded cavity systems. The cavity system allows the implementation of a cellular topology and the use of solid-state RF power amplifiers. The PSB will have 144 cavity cells and amplifiers, and each amplifier uses 17 high-power MOSFETs. The RF systems will be installed in the straight sections where the total ionization dose (TID) is 20 Gy(Si)/year, which may even increase after the upgrade. Research and development work has been performed to validate the use of solid-state amplifiers in this radioactive environment. In this article, we describe a technique to stabilize the solid-state amplifier up to the total dose of about 10 kGy. This technique will enable the use of solid-state amplifiers in even higher radiation environments. The higher sensitivity to the single-event effects (SEEs) of the laterally diffused metal-oxide semiconductors (LDMOS) than to that of the vertical metal–oxide–semiconductor (VMOS) devices is also reported

Magnetic Alloy Loaded Cavities in J-PARC and CERN

Magnetic Alloy loaded cavities have been used in seven synchrotrons in J-PARC and CERN. In this paper, we will review variety of the cavity technologies to satisfy the requirements for the beam acceleration, deceleration, manipulation and instability damping. This paper also contains improvements of cavity cores by magnetic annealing scheme, quality control of cores during production, the cooling methods of magnetic alloy cores: direct water cooling and indirect one using copper discs, control of cavity bandwidths from broad to narrow bands, and the ways to drive RF cavities by tube and rad-hard solid-state amplifiers

RF amplifier using VRF151G and BLF 574 power RF mosfets

Two identical setups, each bearing one RF Mosfet type (VRF151 and BLF574) have been used. The equipment installed in the radiation zone consist of a RF Power amplifier, an RF load, cooling fans and a radiation compensation reference device. The reference device is the same as used for the RF Power amplifier. The irradiated setups, installed in the equipment room, provide adequate RF driving for constant amplitude operation (100W) and frequency sweep from 0.5 MHz to 5 MHz. Compensation for the TID effects on the threshold voltage displacement is derived from the reference device response and applied to the RF Power Amplifier device. The study aimed at evaluating the compensation effectiveness and the degradation of the amplifier characteristics in terms of maximum power, gain and phase variations. During the session, the configuration of CHARM was copper target no shielding hereafter defined as “CuOOOO”

Impedance studies for the PS finemet loaded longitudinal damper

The impedance of the Finemet® loaded longitudinal damper cavity, installed in the CERN Proton Synchrotron straight section 02 during the Long Shutdown 2013-2014, has been evaluated. Time domain simulations with CST Particle Studio have been performed in order to get the lon- gitudinal and transverse impedance of the device and make a comparison with the longitudinal impedance that was mea- sured for a single cell prototype

Dependability Studies for CERN PS Booster RF System Upgrade

Radio frequency systems are a vital part of almost all accelerators. The request for a higher beam bright-ness from the injector chain of CERN's Large Hadron Collider, as demanded by the future High-Luminosity program, has motivated, among many other upgrades, the construction of new RF equipment in the PS Boost-er. Because availability and reliability have an im-portant impact on the luminosity production in a col-lider environment, dependability studies have been performed on the new design of the RF system assum-ing different maintenance strategies. This paper will present the model, made with the commercial software Isograph, for dependability studies. In addition, a comparative study will be presented between the re-sults obtained from Isograph and from an analytical analysis

Longitudinal coupled-bunch oscillation studies in the CERN PS

Longitudinal coupled-bunch oscillations are an important limitation for the high-brightness beams accelerated in the CERN PS. Up to the present intensities they are suppressed by a dedicated feedback system limited to the two dominant oscillation modes. In view of the proposed installation of a wide-band feedback kicker cavity within the framework of the LHC Injectors Upgrade project (LIU), measurements have been performed with the existing damping system with the aim of dimensioning the new one. Following the excitation of well-defined oscillation modes, damping times and corresponding longitudinal kick strengths are analysed. This paper summarizes the results of the observations and gives an outlook on the expected performance with the new coupled-bunch feedback. Copyright © 2013 by JACoW