Assessing Radiology and Radiation Therapy Needs for Cancer Care in Low-and-Middle-Income Countries: Insight From a Global Survey of Departmental and Institutional Leaders.

Purpose: The global cancer burden and mortality rates are increasing, with significant disparities in access to care in low- and middle-income countries (LMICs). This study aimed to identify radiology and radiation therapy needs in LMICs from the perspective of departmental and institutional leaders.

Methods And Materials: A survey was developed and conducted by the American Association of Physicists in Medicine Global Needs Assessment Committee and the American Association of Physicists in Medicine International Council.

Whole-Body Multiparametric PET in Clinical Oncology: Current Status, Challenges, and Opportunities.

The interpretation of clinical oncologic PET studies has historically used static reconstructions based on SUVs. SUVs and SUV-based images have important limitations, including dependence on uptake times and reduced conspicuity of tracer-avid lesions in organs with high background uptake. The acquisition of dynamic PET images enables additional PET reconstructions via Patlak modeling, which assumes that a tracer is irreversibly trapped by tissues of interest.

Performance characteristics of the 5-ring GE Discovery MI PET/CT scanner using AAPM TG-126 report.

Aim: To report on the performance characteristics of the 5-ring GE Discovery MI PET/CT systems using the AAPM TG-126 report and compare these results to NEMA NU 2-2012 where applicable.

Materials And Methods: TG-126 testing was performed on two GE 5-Rings Discovery MI scanners. Tests performed included spatial resolution, PET/CT image-registration accuracy, sensitivity, count rate performance, accuracy of corrections, image contrast, scatter/attenuation correction, and image uniformity.

The first probe of a FLASH proton beam by PET.

The recently observed FLASH effect related to high doses delivered with high rates has the potential to revolutionize radiation cancer therapy if promising results are confirmed and an underlying mechanism understood. Comprehensive measurements are essential to elucidate the phenomenon. We report the first-ever demonstration of measurements of successive in-spill and post-spill emissions of gammas arising from irradiations by a FLASH proton beam.

Dosimetry of a Novel Indium-Labeled Anti-P-Cadherin Monoclonal Antibody (FF-21101) in Non-Human Primates.

P-cadherin is associated with a wide range of tumor types, making it an attractive therapeutic target. FF-21101 is a human-mouse chimeric monoclonal antibody (mAb) directed against human P-cadherin, which has been radioconjugated with indium-111 (In) utilizing a DOTA chelator. We investigated the biodistribution of FF-21101(In) in cynomolgus macaques and extrapolated the results to estimate internal radiation doses of In- and yttrium-90 (Y)-FF-21101 for targeted radioimmunotherapy in humans.

The first PET glimpse of a proton FLASH beam.

We demonstrate the first ever recorded positron-emission tomography (PET) imaging and dosimetry of a FLASH proton beam at the Proton Center of the MD Anderson Cancer Center. Two scintillating LYSO crystal arrays, read out by silicon photomultipliers, were configured with a partial field of view of a cylindrical poly-methyl methacrylate (PMMA) phantom irradiated by a FLASH proton beam. The proton beam had a kinetic energy of 75.

Sequential Targeting of Retinoblastoma and DNA Synthesis Pathways Is a Therapeutic Strategy for Sarcomas That Can Be Monitored in Real Time.

Unlabelled: Treatment strategies with a strong scientific rationale based on specific biomarkers are needed to improve outcomes in patients with advanced sarcomas. Suppression of cell-cycle progression through reactivation of the tumor suppressor retinoblastoma (Rb) using CDK4/6 inhibitors is a potential avenue for novel targeted therapies in sarcomas that harbor intact Rb signaling. Here, we evaluated combination treatment strategies (sequential and concomitant) with the CDK4/6 inhibitor abemacicib to identify optimal combination strategies.

The potential of biology-guided radiation therapy in thoracic cancer: A preliminary treatment planning study.

Purpose: We investigated the feasibility of biology-guided radiotherapy (BgRT), a technique that utilizes real-time positron emission imaging to minimize tumor motion uncertainties, to spare nearby organs at risk.

Methods: Volumetric modulated arc therapy (VMAT), intensity-modulated proton (IMPT) therapy, and BgRT plans were created for a paratracheal node recurrence (case 1; 60 Gy in 10 fractions) and a primary peripheral left upper lobe adenocarcinoma (case 2; 50 Gy in four fractions).

Results: For case 1, BgRT produced lower bronchus V40 values compared to VMAT and IMPT.

Prevalence and Molecular Mechanisms of Carbapenem Resistance among Gram-Negative Bacilli in Three Hospitals of Northern Lebanon.

Carbapenem resistance (CR) is an emerging health issue. Epidemiological surveys on carbapenem-resistant Gram-negative bacilli (CR-GNB) in Lebanon remain scarce. In this study, we determined the prevalence of CR-GNB isolated between 2015 to 2019 in three hospitals in northern Lebanon: 311 CR- (out of 11210; 2.

Impact of low injected activity on data driven respiratory gating for PET/CT imaging with continuous bed motion.

Data driven respiratory gating (DDG) in positron emission tomography (PET) imaging extracts respiratory waveforms from the acquired PET data obviating the need for dedicated external devices. DDG performance, however, degrades with decreasing detected number of coincidence counts. In this paper, we assess the clinical impact of reducing injected activity on a new DDG algorithm designed for PET data acquired with continuous bed motion (CBM_DDG) by evaluating CBM_DDG waveforms, tumor quantification, and physician's perception of motion blur in resultant images.

Impact of acquisition time and misregistration with CT on data-driven gated PET.

. Data-driven gating (DDG) can address patient motion issues and enhance PET quantification but suffers from increased image noise from utilization of <100% of PET data. Misregistration between DDG-PET and CT may also occur, altering the potential benefits of gating.

Delayed FDG PET Provides Superior Glioblastoma Conspicuity Compared to Conventional Image Timing.

Glioblastomas are malignant, often incurable brain tumors. Reliable discrimination between recurrent disease and treatment changes is a significant challenge. Prior work has suggested glioblastoma FDG PET conspicuity is improved at delayed time points vs.

A Path to Qualification of PET/MRI Scanners for Multicenter Brain Imaging Studies: Evaluation of MRI-Based Attenuation Correction Methods Using a Patient Phantom.

PET/MRI scanners cannot be qualified in the manner adopted for hybrid PET/CT devices. The main hurdle with qualification in PET/MRI is that attenuation correction (AC) cannot be adequately measured in conventional PET phantoms because of the difficulty in converting the MR images of the physical structures (e.g.

Guidelines on Setting Up Stations for Remote Viewing of Nuclear Medicine and Molecular Imaging Studies During COVID-19.

The current pandemic has created a situation where nuclear medicine practitioners and medical physicists read or process nuclear medicine images remotely from their home office. This article presents recommendations on the components and specifications when setting up a remote viewing station for nuclear medicine imaging.

PET/CT acceptance testing and quality assurance: Executive summary of AAPM Task Group 126 Report.

Purpose: A Positron Emission Tomography/Computed Tomography quality assurance program is necessary to ensure that patients receive optimal imaging and care. We summarize the AAPM Task Group (TG) 126 report on acceptance and quality assurance (QA) testing of PET/CT systems.

Methods: TG 126 was charged with developing PET/CT acceptance testing and QA procedures.

Phase I Study of P-cadherin-targeted Radioimmunotherapy with Y-FF-21101 Monoclonal Antibody in Solid Tumors.

Purpose: Y-FF-21101 is an Yttrium-90-conjugated, chimeric mAb that is highly specific for binding to human placental (P)-cadherin, a cell-to-cell adhesion molecule overexpressed and associated with cancer invasion and metastatic dissemination in many cancer types. We report the clinical activity of Y-FF-21101 in a first-in-human phase I study in patients with advanced solid tumors.

Patients And Methods: The safety and efficacy of Y-FF-21101 were evaluated in a phase I 3+3 dose-escalation study in patients with advanced solid tumors ( = 15) over a dose range of 5-25 mCi/m.

What scans we will read: imaging instrumentation trends in clinical oncology.

Oncological diseases account for a significant portion of the burden on public healthcare systems with associated costs driven primarily by complex and long-lasting therapies. Through the visualization of patient-specific morphology and functional-molecular pathways, cancerous tissue can be detected and characterized non-invasively, so as to provide referring oncologists with essential information to support therapy management decisions. Following the onset of stand-alone anatomical and functional imaging, we witness a push towards integrating molecular image information through various methods, including anato-metabolic imaging (e.

Systematic and random errors of PET-based Y 3D dose quantification.

Purpose: The objective was to characterize both systematic and random errors in Positron Emission Tomography (PET)-based Y three-dimensional (3D) dose quantification.

Methods: A modified NEMA-IEC phantom was used to emulate Y-microsphere PET imaging conditions: sphere activity concentrations of 1.6 and 4.

Improved Alignment of PET and CT Images in Whole-Body PET/CT in Cases of Respiratory Motion During CT.

Respiratory motion during the CT and PET parts of a PET/CT scan leads to imperfect alignment of anatomic features seen by the 2 modalities. In this work, we concentrate on the effects of motion during CT. We propose a novel approach for improving the alignment.

Characterization of continuous bed motion effects on patient breathing and respiratory motion correction in PET/CT imaging.

Continuous bed motion (CBM) was recently introduced as an alternative to step-and-shoot (SS) mode for PET/CT data acquisition. In CBM, the patient is continuously advanced into the scanner at a preset speed, whereas in SS, the patient is imaged in overlapping bed positions. Previous investigations have shown that patients preferred CBM over SS for PET data acquisition.

Mechanism-Specific Pharmacodynamics of a Novel Complex-I Inhibitor Quantified by Imaging Reversal of Consumptive Hypoxia with [F]FAZA PET .

Tumors lack a well-regulated vascular supply of O and often fail to balance O supply and demand. Net O tension within many tumors may not only depend on O delivery but also depend strongly on O demand. Thus, tumor O consumption rates may influence tumor hypoxia up to true anoxia.

Radiomics features of the primary tumor fail to improve prediction of overall survival in large cohorts of CT- and PET-imaged head and neck cancer patients.

Radiomics studies require many patients in order to power them, thus patients are often combined from different institutions and using different imaging protocols. Various studies have shown that imaging protocols affect radiomics feature values. We examined whether using data from cohorts with controlled imaging protocols improved patient outcome models.

Effects of alterations in positron emission tomography imaging parameters on radiomics features.

Radiomics studies require large patient cohorts, which often include patients imaged using different imaging protocols. We aimed to determine the impact of variability in imaging protocol parameters and interscanner variability using a phantom that produced feature values similar to those of patients. Positron emission tomography (PET) scans of a Hoffman brain phantom were acquired on GE Discovery 710, Siemens mCT, and Philips Vereos scanners.

Task Group 174 Report: Utilization of [ F]Fluorodeoxyglucose Positron Emission Tomography ([ F]FDG-PET) in Radiation Therapy.

The use of positron emission tomography (PET) in radiation therapy (RT) is rapidly increasing in the areas of staging, segmentation, treatment planning, and response assessment. The most common radiotracer is F-fluorodeoxyglucose ([ F]FDG), a glucose analog with demonstrated efficacy in cancer diagnosis and staging. However, diagnosis and RT planning are different endeavors with unique requirements, and very little literature is available for guiding physicists and clinicians in the utilization of [ F]FDG-PET in RT.

Quality Improvement Initiatives to Assess and Improve PET/CT Injection Infiltration Rates at Multiple Centers.

PET/CT radiotracer infiltration is not uncommon and is often outside the imaging field of view. Infiltration can negatively affect image quality, image quantification, and patient management. Until recently, there has not been a simple way to routinely practice PET radiopharmaceutical administration quality control and quality assurance.