Navigating The Prostate Cancer Frontier: A Bibliometric and Altmetric Analysis of [225Ac]Ac-PSMA Therapy.

The main aim of this study was to evaluate the current state of bibliometric and altmetric research output of [225Ac]Ac-Prostate specific membrane antigen (PSMA) and its implications for prostate cancer (PC). Both PubMed and Scopus digital libraries were systematically explored to retrieve relevant data on the topic of interest. The study of various bibliometric and altmetric indices was facilitated through the use of Microsoft Excel, Stata (Version 17.0), and VOSviewer (Version 1.6) Softwares. The parameters included in this study comprised the examination of published articles, annual trends, countries, institutions, authors, journals, and co-occurring keywords. From 2014 to 2024, our study examined a total of 100 publications within the given domain. The studies that received the highest citations primarily centered on the crucial topic of metastatic castration-resistant prostate cancer, with a particular emphasis on evaluating the safety and effectiveness of [225Ac]Ac-PSMA therapy. Moreover, much scholarly inquiry has been devoted to examining the [225Ac]Ac-PSMA adverse effects. Three high prolific countries (namely, Germany, United States, and South Africa) dominated the research render in terms of publications and citations. Finally, A strong correlation was observed between altmetric score and citation number (P < 0.001). The observed surge in scholarly research output and altmetric indicators associated with [225Ac]Ac-PSMA signifies a shift in emphasis towards embracing alpha targeted therapy in PC.

Does enzalutamide related PSMA upregulation affect outcomes of lutetium-177 PSMA radioligand therapy?

BACKGROUND: Enzalutamide is an antiandrogen drug used prior to lutetium-177 prostate specific membrane antigen (Lu-PSMA) radioligand therapy and has shown promising results for upregulating the PSMA expression on prostate cancer cells. In this study, we aim to compare prostate specific antigen (PSA) level changes in prostate cancer patients who received enzalutamide to those who did not. METHODS: Prostate cancer patients who underwent Lu-PSMA between 2021 and 2023 were retrospectively included. Patients were grouped based on prior enzalutamide therapy: those who received enzalutamide (EZ+) for at least 14 days and those who did not (EZ-). PSA changes and F-18 DCFPyL SUV (Standardized Uptake Values) were compared. RESULTS: Thirty-seven patients were included, 18 EZ+ and 19 EZ-. The median age, Gleason score, and prior chemo/hormonal therapies were similar for EZ+ and EZ-, except for radium-223. Eleven patients (61%) in EZ+ and 13 patients (68%) in EZ- showed a decrease in PSA after the first cycle (p = 0.64). Four patients (22%) in EZ+ and seven patients (37%) in EZ- had more than 50% decrease in PSA after the first cycle (p = 0.33). The average percent decline at the end of the treatment was 23.3% in EZ+ and 50.4% in EZ- (p = 0.4). There was no difference in terms of lesion with highest SUVmax, mean SUV, total tumor volume or activity on pre-therapy PSMA imaging. CONCLUSION: Enzalutamide treatment prior to Lu-PSMA does not improve patient outcomes when applied remotely. Larger studies evaluating the combination therapies and the timing of enzalutamide are needed to assess its correlation with Lu-PSMA outcomes.

18F-FDG PET/CT in left ventricular assist device infections: In-depth characterization and clinical implications.

BACKGROUND: Previous retrospective studies suggest a good diagnostic performance of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET)/computed tomography (CT) in left ventricular assist device (LVAD) infections. Our aim was to prospectively evaluate the role of PET/CT in the characterization and impact on clinical management of LVAD infections. METHODS: A total of 40 patients (aged 58 [53-62] years) with suspected LVAD infection and 5 controls (aged 69 [64-71] years) underwent 18F-FDG-PET/CT. Four LVAD components were evaluated: exit site and subcutaneous driveline (peripheral), pump pocket, and outflow graft. The location with maximal uptake was considered the presumed site of infection. Infection was confirmed by positive culture (exit site or blood) and/or surgical findings. RESULTS: Visual uptake was present in 40 patients (100%) in the infection group vs 4 (80%) control subjects. For each individual component, the presence of uptake was more frequent in the infection than in the control group. The location of maximal uptake was most frequently the pump pocket (48%) in the infection group and the peripheral components (75%) in the control group. Maximum standard uptake values (SUVmax) were higher in the infection than in the control group: SUVmax (average all components): 6.9 (5.1-8.5) vs 3.8 (3.7-4.3), p = 0.002; SUVmax (location of maximal uptake): 10.6 ± 4.0 vs 5.4 ± 1.9, p = 0.01. Pump pocket infections were more frequent in patients with bacteremia than without bacteremia (79% vs 31%, p = 0.011). Pseudomonas (32%) and methicillin-susceptible Staphylococcus aureus (29%) were the most frequent pathogens and were associated with pump pocket infections, while Staphylococcus epidermis (11%) was associated with peripheral infections. PET/CT affected the clinical management of 83% of patients with infection, resulting in surgical debridement (8%), pump exchange (13%), and upgrade in the transplant listing status (10%), leading to 8% of urgent transplants. CONCLUSIONS: 18F-FDG-PET/CT enables the diagnosis and characterization of the extent of LVAD infections, which can significantly affect the clinical management of these patients.

ACR-ACNM-ARS-ASTRO-SNMMI Practice Parameter for the Performance of Therapy With Radiopharmaceuticals.

OBJECTIVES: This practice parameter was revised collaboratively by the American College of Radiology (ACR), the American College of Nuclear Medicine, the American Radium Society, the American Society for Radiation Oncology, and the Society of Nuclear Medicine and Molecular Imaging. The document is intended to serve as a resource for appropriately trained and licensed physicians who perform therapeutic procedures with unsealed sources, referred to in the document using the more inclusive terminology of radiopharmaceuticals, for which a written directive is required for authorized users under NRC 10 CFR 35.300. METHODS: This practice parameter was developed according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website ( https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards ) by the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the American Radium Society. RESULTS: This practice parameter addresses the overall role of the applicable physician-authorized user, Qualified Medical Physicist, and other specialized personnel involved in the delivery of radiopharmaceutical therapy. Therapeutic radiopharmaceuticals include those administered as elemental radioactive isotopes (radionuclides) or the radioactive element incorporated into a targeting molecule (ligand) by one or more chemical bonds. This document provides guidance regarding general principles of radionuclide therapies and indications of various alpha, beta, gamma, and mixed emission agents with references to several recent practice parameters on new and commonly performed radiopharmaceutical therapies. CONCLUSION: This document addresses clinical circumstances, elements of available agents, and the qualifications and responsibilities of various members of the radiation care team, specifications of consultation and other clinical documentation, post-therapy follow-up, radiation safety precautions, elements of quality control and improvement programs, infection control, and patient education to ensure optimal patient care and safety when utilizing radiopharmaceuticals.

The diagnostic accuracy of perfusion-only scan in the diagnosis of pulmonary embolism in the era of COVID-19: A single-center study of 434 patients.

INTRODUCTION: There is a paucity of data in the literature regarding the diagnostic accuracy of perfusion (Q)-only studies in the absence of ventilation images. This study aims to assess the diagnostic accuracy of Q-only imaging in the pandemic era. METHODS: Patients who underwent Q-only imaging for pulmonary embolism between March 2020 and February 2021 were analyzed. Patients who underwent lung quantification analysis were excluded. Q-only test results were reported as per modified PIOPED II criteria and single positron emission tomography/computed tomography (SPECT/CT) imaging was performed as needed. Patients were considered concordant or discordant by correlating the Q-only results with CT angiogram (CTA) or clinical diagnosis made through chart review. The diagnostic accuracy was calculated after excluding intermediate probability and nondiagnostic studies. RESULTS: Four hundred and thirty-four patients were identified. One hundred and twenty-eight patients (29.4%) underwent ultrasound Doppler, 37 patients (8.5%) underwent CTA, and 16 patients (3.6%) underwent both. After excluding patients with intermediate probability or nondiagnostic studies and who did not have follow-up (a total of 87 patients [20%]), 347 patients were enrolled in the final analysis. The combined planar and SPECT/CT sensitivity and specificity were 85.4% (72.2%-93.9% confidence interval [CI]) and 98.7% (96.9%-98.6% CI), respectively. The positive predictive value (PPV) of the Q-only imaging was 89.1% (77.3%-95.1% CI) and the negative predictive value (NPV) was 98.2% (96.4%-99% CI). The sensitivity with SPECT/CT reached 100% (CI: 71.5%-100%) with a specificity of 92.3% (CI: 64%-99.8%). The PPV was 85.7% (CI: 62.1%-95.6%) and the NPV was 100%. CONCLUSION: Q-only imaging provides clinically acceptable results. The sensitivity of the Q-only scan is increased when coupled with SPECT/CT.

FDG-PET/MRI for the preoperative diagnosis and staging of peritoneal carcinomatosis: a prospective multireader pilot study.

PURPOSE: To assess the diagnostic performance of FDG-PET/MRI for the preoperative diagnosis and staging of peritoneal carcinomatosis (PC) using surgical Sugarbaker's PC index (PCI) as the reference in a multireader pilot study. METHODS: Fourteen adult patients (M/F: 3/11, mean age: 57 ± 12 year) with PC were prospectively included in this single-center study. Patients underwent FDG-PET/MRI prior to surgery (mean delay: 14 d, range: 1-63 d). Images were reviewed independently by 2 abdominal radiologists and 2 nuclear medicine physicians. The radiologists assessed contrast-enhanced abdominal MR images, while the nuclear medicine physicians assessed PET images fused with T2-weighted images. The abdomen was divided in 13 regions, scored from 0 to 3. A hybrid FDG-PET/MRI radiological PCI was created by combining the study data. Radiological PCI was compared to the surgical PCI on a per-patient and per-region basis. Inter-reader agreement was evaluated. RESULTS: Mean surgical PCI was 10 ± 8 (range: 0-24). Inter-reader agreement was almost perfect for all sets for radiologic PCI (Kappa: 0.81-0.98). PCI scores for all reading sets significantly correlated with the surgical PCI score (r range: 0.57-0.74, p range: < 0.001-0.003). Pooled per-patient sensitivity, specificity, and accuracy were 75%/50%/71.4% for MRI, 66.7%/50%/64.3% for FDG-PET, and 91.7%/50%/85.7% for FDG-PET/MRI, without significant difference (p value range 0.13-1). FDG-PET/MRI achieved 100% sensitivity and 100% specificity for a cutoff PCI of 20. Per-region sensitivity and accuracy were lower: 37%/61.8% for MRI, 17.8%/64.3% for FDG-PET, and 52.7%/60.4% for FDG-PET/MRI, with significantly higher sensitivity for FDG-PET/MRI. Per-region specificity was higher for FDG-PET (95%) compared to MRI (78.4%) and FDG-PET/MRI (66.5%). CONCLUSION: FDG-PET/MRI achieved an excellent diagnostic accuracy per-patient and weaker performance per-region for detection of PC. The added value of PET/MRI compared to MRI and FDG-PET remains to be determined.

The Mount Sinai Clinical Pathway for the Diagnosis and Management of Hypercortisolism due to Ectopic ACTH Syndrome.

Neoplasms that secrete ectopic adrenocorticotropin (ACTH) may cause severe, life-threatening hypercortisolism. These tumors are often difficult to localize and treat, requiring a comprehensive and systematic management plan orchestrated by a multidisciplinary team. The Mount Sinai Adrenal Center hosted an interdisciplinary retreat of experts in adrenal disorders and neuroendocrine tumors (NETs) with the aim of developing a clinical pathway for the management of Cushing syndrome due to ectopic ACTH production. The result was institutional recommendations for the diagnosis, localization, surgical approaches to intrathoracic tumors and bilateral adrenalectomy, and perioperative and postoperative medical management of hypercortisolism and its sequelae. Specific recommendations were made regarding the timing and selection of therapies based on the considerations of our team as well as a review of the current literature. Our clinical pathway can be applied by other institutions directly or serve as a guide for institution-specific management.

Joint EANM, SNMMI, and IAEA Enabling Guide: How to Set up a Theranostics Center.

The theranostics concept using the same target for both imaging and therapy dates back to the middle of the last century, when radioactive iodine was first used to treat thyroid diseases. Since then, radioiodine has become broadly established clinically for diagnostic imaging and therapy of benign and malignant thyroid disease, worldwide. However, only since the approval of SSTR2-targeting theranostics following the NETTER-1 trial in neuroendocrine tumors, and the positive outcome of the VISION trial has theranostics gained substantial attention beyond nuclear medicine. The roll-out of radioligand therapy for treating a high-incidence tumor such as prostate cancer requires the expansion of existing and the establishment of new theranostics centers. Despite wide global variation in the regulatory, financial and medical landscapes, this guide attempts to provide valuable information to enable interested stakeholders to safely initiate and operate theranostic centers. This enabling guide does not intend to answer all possible questions, but rather to serve as an overarching framework for multiple, more detailed future initiatives. It recognizes that there are regional differences in the specifics of regulation of radiation safety, but common elements of best practice valid globally.

Joint EANM, SNMMI and IAEA enabling guide: how to set up a theranostics centre.

The theranostics concept using the same target for both imaging and therapy dates back to the middle of the last century, when radioactive iodine was first used to treat thyroid diseases. Since then, radioiodine has become broadly established clinically for diagnostic imaging and therapy of benign and malignant thyroid disease, worldwide. However, only since the approval of SSTR2-targeting theranostics following the NETTER-1 trial in neuroendocrine tumours and the positive outcome of the VISION trial has theranostics gained substantial attention beyond nuclear medicine. The roll-out of radioligand therapy for treating a high-incidence tumour such as prostate cancer requires the expansion of existing and the establishment of new theranostics centres. Despite wide global variation in the regulatory, financial and medical landscapes, this guide attempts to provide valuable information to enable interested stakeholders to safely initiate and operate theranostics centres. This enabling guide does not intend to answer all possible questions, but rather to serve as an overarching framework for multiple, more detailed future initiatives. It recognizes that there are regional differences in the specifics of regulation of radiation safety, but common elements of best practice valid globally.

Tumour-to-normal tissue (T/N) dosimetry ratios role in assessment of 90Y selective internal radiation therapy (SIRT).

OBJECTIVE: The purpose of our work is to assess the role of tumour-to-normal tissue (T/N) dosimetry ratios for predicting response in patients undergoing locoregional therapy to the liver with 90Y microspheres. METHODS: A total of 39 patients (7 female:32 male, mean age 68.3 ± 7.6 years), underwent positron emission tomography (PET)/CT imaging after treatment with 90Y microspheres. For attenuation correction and localization of the 90Y microspheres, the low-dose, non-diagnostic CT images from PET/CT were used. The acquisition took 15 min and the reconstruction matrix size was 200 × 200 × 75 mm and voxel size of 4.07 × 4.07 × 3.00 mm. For dosimetry calculations, the local deposition method with known activity of 90Y was used. For each patient, regions of interest for tumour(s) and whole liver were manually created; the normal tissue region of interest was created automatically. mRECIST criteria on MRI done at 1 month post-treatment and subsequently every 3 months after 90Y treatment, were used to assess response. RESULTS: For 39 patients, the mean liver, tumour and normal tissue doses (mean ± SD) were, 55.17 ± 26.04 Gy, 911.87 ± 866.54 Gy and 47.79 ± 20.47 Gy, respectively. Among these patients, 31 (79%) showed complete response (CR) and 8 (21%) showed progression of disease (PD). For patients with CR, the mean T/N dose ratio obtained was 24.91 (range 3.09-80.12) and for patients with PD, the mean T/N dose ratio was significantly lower, at 6.69 (range 0.36-14.75). CONCLUSION: Our data show that patients with CR have a statistically higher T/N dose ratio than those with PD. Because, the number of PD cases was limited and partial volume effect was not considered, further investigation is warranted. ADVANCES IN KNOWLEDGE: T/N dosimetry ratios can be used for assessing response in patients undergoing locoregional therapy to the liver with 90Y microspheres.

Asymptomatic SARS-CoV-2 infection: Incidental findings on FDG PET/CT.

RATIONALE AND OBJECTIVES: Identify the incidental findings of Covid-19 pneumonitis on 18F-FDG PET/CT scan in asymptomatic oncologic patients. The goal was to detect clinically unsuspected Covid-19 infections to prevent community spread. MATERIALS AND METHODS: Retrospective analysis was conducted to recognize the pattern of metabolic and radiographic alterations on 18F-FDG PET/CT scans in Covid-19 patients. 492 18F-FDG PET/CT scans were reviewed for pulmonary and systemic abnormalities. RESULTS: 18F-FDG PET/CT demonstrated new lung infiltrates in 29 asymptomatic patients. 13/29 patients had Covid-19 infection confirmed by nasopharyngeal nucleic acid PCR test. The most common lung abnormality was pure ground-glass opacity (GGO) (90%) in peripheral distribution (100%), involving 1 lobe in four patients (30.8%), 2-3 lobes in four patients, and 4-5 lobes in five patients (38.4%). Mean SUVmax was 4.7 (range 1.3-13.1). Ten patients developed symptoms, mainly fever, fatigue, and dry cough, within 6.4 ± 7.8 days (range 1-24). Of the available laboratory data of 12 patients, eight developed lymphopenia, and five patients had neutrophilia. Five patients required hospitalization, and two died of complications. CONCLUSION: For a given geographic region in the later stage of a pandemic, such as Covid-19, community spread of the disease is common. Therefore, it is not surprising to find it in asymptomatic being imaged for other indications. Recognition of its manifestation and effectively mounting mitigation protocols is essential to further reduce SARS-CoV-2 spread, especially to susceptible groups, predominantly the elderly and people with comorbidities.

Multimodality Imaging of Myocardial Viability.

PURPOSE OF REVIEW: Myocardial viability is an important pathophysiologic concept which may have significant clinical impact in patients with left ventricular dysfunction due to ischemic heart disease. Understanding the imaging modalities used to assess viability, and the clinical implication of their findings, is critical for clinical decision-making in this population. RECENT FINDINGS: The ability of dobutamine echocardiography, single-photon emission computed tomography, positron emission tomography, and cardiac magnetic resonance imaging to predict functional recovery following revascularization is well-established. Despite different advantages and disadvantages for each imaging modality, each modality has demonstrated reasonable performance characteristics in identifying viable myocardium. Recent data, however, has called into question whether this functional recovery leads to improved clinical outcomes. Although the assessment of viability can be used to aid in clinical decision-making prior to revascularization, its broad application to all patients is limited by a lack of data confirming improvement in clinical outcomes. Thus, viability assessments may be best applied to select patients (such as those with increased surgical risk) and integrated with clinical, laboratory, and imaging data to guide clinical care. Future research efforts should be aimed at establishing the impact of viability on clinical outcomes.