Quality assurance of the inter-spot beam delivery of a dose driven continuous scanning proton therapy system.

Background: Dose-driven continuous scanning (DDCS) is a type of beam delivery in Hitachi pencil beam scanning (PBS) particle therapy system. Particle beam is irradiated continuously between spots to achieve a higher effective dose rate and a shorter beam delivery time. The beam is only turned off at break spots, the end of a treatment layer and during spill change.

Factors that influence unproven stem cell intervention seeking behavior: A qualitative analysis of U.S. patients considering or having undertaken unproven stem cell interventions.

Chronic disease patients seeking information about unproven stem cell interventions (SCIs) routinely encounter misinformation. Identifying differences among patients with little interest in unproven SCIs (low seekers) from those with high interest (high seekers) would help in developing patient communication interventions. This study characterizes patient knowledge, information sources, attitudes, and emotion of 36 patients and carers through in-depth interviews and reports three themes: knowledge; attitudes about safety, efficacy and expectations; and desperation.

A comprehensive characterization of the temporal characteristics of dose driven continuous scanning in proton therapy.

To comprehensively characterize the temporal characteristics of dose-driven continuous scanning (DDCS) proton therapy system including the rise time to nominal beam current (trise), minimum time between break spot (tb), beam current fluctuation and the flap dose.Measurements were performed on a Hitachi proton therapy synchrotron. The beam current fluctuation was measured using a 20 kHz 2D strip ionization chamber (CROSSmini) with a fixed point irradiation without break points (BPs).

Toward equitable regenerative medicine: a health equity research framework for emerging regenerative treatments.

Regenerative medicine continues to advance rapidly, yet research examining health disparities within this field remains notably limited. The distinctive characteristics of regenerative therapies - complex manufacturing, specialized delivery, and personalized approaches - present unique challenges for equitable health care access beyond traditional disparities. This gap is concerning as many conditions targeted by regenerative treatments disproportionately affect underserved populations.

Real-time gated proton therapy: Introducing clinical workflow and failure modes and effects analysis (FMEA).

Introduction: Real-Time Gated Proton Therapy (RGPT) has been used in proton therapy to mitigate respiratory motion challenges. This study presents the first comprehensive description of the RGPT clinical workflow at the National Cancer Centre Singapore (NCCS) and introduces a novel Failure Modes and Effects Analysis (FMEA) for RGPT.

Methods: We detail the workflow for prostate and liver/lung proton treatments.

An analysis of stem cell training programs for physicians in the US-A mirage of credibility.

Analyzing stem cell training businesses for United States (US) physicians shows the use of sensationalized marketing language emphasizing profits and growth with many of the instructors affiliated with clinics providing unproven therapies. We argue that many current pedagogical offerings for physicians interested in stem cell interventions are likely to offer questionable training and outline red flags for physicians interested in stem cell therapies.

Call for a Translational Orthobiologics Fellowship in the Era of Regenerative Medicine.

Regenerative medicine is a rapidly advancing field, particularly within the field of physical medicine and rehabilitation. While orthobiologics are currently being used in clinical practice, there remains a need for high-quality clinical trials and translational research to standardize treatments and improve patient outcomes. Education is vital for streamlining development of evidence-based, practical, and effective treatments.

Evaluation of Spin in Clinical Trials of Mesenchymal Stromal Cells for the Treatment of Knee Osteoarthritis: A Systematic Review.

Background: The regenerative potential of mesenchymal stromal cells (MSCs) has sparked interest in their use for knee osteoarthritis. Concurrently, there have been investigations on how data in scientific journals are reported and how they may influence readers' interpretations, or "spin bias." These studies are at risk for bias, given the limited number of patients and inconsistent blinding or controls.

Denoising proton reference dosimetry spectrum using a large area ionization chamber-physical basis and type A uncertainty.

Reference dosimetry measurement in a pencil beam scanning system can exhibit dose fluctuation due to intra-spill spot positional drift. This results in a noisy reference dosimetry measurement against energy which could introduce errors in monitor unit calibration. The aim of this study is to investigate the impact of smoothing the reference dosimetry measurements on the type A uncertainty.

A treatment-site-specific evaluation of commercial synthetic computed tomography solutions for proton therapy.

Background And Purpose: Despite the superior dose conformity of proton therapy, the dose distribution is sensitive to daily anatomical changes, which can affect treatment accuracy. This study evaluated the dose recalculation accuracy of two synthetic computed tomography (sCT) generation algorithms in a commercial treatment planning system.

Materials And Methods: The evaluation was conducted for head-and-neck, thorax-and-abdomen, and pelvis sites treated with proton therapy.

Descriptions of Scientific Evidence and Uncertainty of Unproven COVID-19 Therapies in US News: Content Analysis Study.

Background: Politicization and misinformation or disinformation of unproven COVID-19 therapies have resulted in communication challenges in presenting science to the public, especially in times of heightened public trepidation and uncertainty.

Objective: This study aims to examine how scientific evidence and uncertainty were portrayed in US news on 3 unproven COVID-19 therapeutics, prior to the development of proven therapeutics and vaccines.

Methods: We conducted a media analysis of unproven COVID-19 therapeutics in early 2020.

Proton Beam Range and Charge Verification Using Multilayer Faraday Collector.

Purpose: A daily quality assurance (QA) check in proton therapy is ensuring that the range of each proton beam energy in water is accurate to 1 mm. This is important for ensuring that the tumor is adequately irradiated while minimizing damage to surrounding healthy tissue. It is also important to verify the total charge collected against the beam model.

Real-time gated proton therapy with a reduced source to imager distance: Commissioning and quality assurance.

Introduction: Real-time gated proton therapy (RGPT) is a motion management technique unique to the Hitachi particle therapy system. It uses pulsed fluoroscopy to track an implanted fiducial marker. There are currently no published guidelines on how to conduct the commissioning and quality assurance.

Repurposing DailyQA3 for an efficient and spot position sensitive daily quality assurance tool for proton therapy.

Introduction: Daily quality assurance is an integral part of a radiotherapy workflow to ensure the dose is delivered safely and accurately to the patient. It is performed before the first treatment of the day and needs to be time and cost efficient for a multiple gantries proton center. In this study, we introduced an efficient method to perform QA for output constancy, range verification, spot positioning accuracy and imaging and proton beam isocenter coincidence with DailyQA3.

First clinical experience following the consensus guide for calibrating a proton stopping power ratio curve in a new proton centre.

Background And Purpose: This work introduces the first assessment of CT calibration following the ESTRO's consensus guidelines and validating the HLUT through the irradiation of biological material.

Methods: Two electron density phantoms were scanned with two CT scanners using two CT scan energies. The stopping power ratio (SPR) and mass density (MD) HLUTs for different CT scan energies were derived using Schneider's and ESTRO's methods.

Pulsed low-dose rate radiotherapy for recurrent bone sarcomas: case reports and brief review.

Purpose: Re-irradiation for bulky recurrent sarcoma carries significant risks. Pulsed low-dose rate radiotherapy (PLDR) is an attractive option for re-irradiation due to inherent radiobiological advantages.

Materials And Methods: We present two patients who underwent reirradiation using PLDR technique, followed by a literature review.

Effects of modern aesthetic dental fillings on proton therapy.

Background And Purpose: High-density dental fillings pose a non-negligible impact on head and neck cancer treatment. For proton therapy, stopping power ratio (SPR) prediction will be significantly impaired by the associated image artifacts. Dose perturbation is also inevitable, compromising the treatment plan quality.

US state laws on medical freedom and investigational stem cell procedures: a call to focus on state-based legislation.

The premature marketing of investigational stem cell interventions (SCIs) is a growing market in the US. Several US states have passed legislation to permit and promote unproven and experimental SCIs for individuals with terminal or chronic diseases. These SCI medical freedom laws, which are largely based on right-to-try legislation, increase access to experimental SCIs with little to no oversight.

Implementing dispersion measurement as part of scanning proton therapy commissioning and quality assurance.

. Dispersion in an accelerator quantifies the deviation of the proton trajectory when there is a momentum deviation. We present for the first time a safe method of measuring dispersion in the clinic, using a scintillator detector and the momentum deviations within a spill.

The effect of spill change on reliable absolute dosimetry in a synchrotron proton spot scanning system.

Background: Absolute dosimetry measurement is an integral part of Treatment Planning System (TPS) commissioning and it involves measuring the integrated absorbed dose to water for all energies in a pencil beam scanning delivery system. During the commissioning of Singapore's first proton therapy center, a uniform scanned field with an Advanced Markus chamber method was employed for this measurement, and a large dose fluctuation of at least 5% was observed for 10% of the energy layers during repeated measurements.

Purpose: This study aims to understand the root cause of this fluctuation by relating the actual delivered spot information in the log file with the charge measurement by the ion chambers.

ISSCR Education Committee syllabus and learning guide for enhancing stem cell literacy.

The rapidly evolving stem cell field puts much stress on developing educational resources. The ISSCR Education Committee has created a flexible stem cell syllabus rooted in core concepts to facilitate stem cell literacy. The free syllabus will be updated regularly to maintain accuracy and relevance.