Safety Monitoring of COVID-19 Vaccines in Persons with Prior SARS-CoV-2 Infection: A European Multi-Country Study.

In all pivotal trials of COVID-19 vaccines, the history of previous SARS-CoV-2 infection was mentioned as one of the main exclusion criteria. In the absence of clinical trials, observational studies are the primary source for evidence generation. This study aims to describe the patient-reported adverse drug reactions (ADRs) following the first COVID-19 vaccination cycle, as well as the administration of booster doses of different vaccine brands, in people with prior SARS-CoV-2 infection, as compared to prior infection-free matched cohorts of vaccinees. A web-based prospective study was conducted collecting vaccinee-reported outcomes through electronic questionnaires from eleven European countries in the period February 2021-February 2023. A baseline questionnaire and up to six follow-up questionnaires collected data on the vaccinee's characteristics, as well as solicited and unsolicited adverse reactions. Overall, 3886 and 902 vaccinees with prior SARS-CoV-2 infection and having received the first dose or a booster dose, respectively, were included in the analysis. After the first dose or booster dose, vaccinees with prior SARS-CoV-2 infection reported at least one ADR at a higher frequency than those matched without prior infection (3470 [89.6%] vs. 2916 [75.3%], and 614 [68.2%] vs. 546 [60.6%], respectively). On the contrary side, after the second dose, vaccinees with a history of SARS-CoV-2 infection reported at least one ADR at a lower frequency, compared to matched controls (1443 [85.0%] vs. 1543 [90.9%]). The median time to onset and the median time to recovery were similar across all doses and cohorts. The frequency of adverse reactions was higher in individuals with prior SARS-CoV-2 infection who received Vaxzevria as the first dose and Spikevax as the second and booster doses. The frequency of serious ADRs was low for all doses and cohorts. Data from this large-scale prospective study of COVID-19 vaccinees could be used to inform people as to the likelihood of adverse effects based on their history of SARS-CoV-2 infection, age, sex, and the type of vaccine administered. In line with pivotal trials, the safety profile of COVID-19 vaccines was also confirmed in people with prior SARS-CoV-2 infection.

Frequency and timing of adverse reactions to COVID-19 vaccines; A multi-country cohort event monitoring study.

INTRODUCTION: During the COVID-19 pandemic, EMA set-up a large-scale cohort event monitoring (CEM) system to estimate incidence rates of patient-reported adverse drug reactions (ADRs) of different COVID-19 vaccines across the participating countries. This study aims to give an up to date and in-depth analysis of the frequency of patient-reported ADRs after the 1st, 2nd, and booster vaccination, to identify potential predictors in developing ADRs and to describe time-to-onset (TTO) and time-to-recovery (TTR) of ADRs. METHODS: A CEM study was rolled out in a period ranging from February 2021 to February 2023 across multiple European countries; The Netherlands, Belgium, France, the United Kingdom, Italy, Portugal, Romania, Slovakia and Spain. Analysis consisted of a descriptive analyses of frequencies of COVID-19 vaccine-related ADRs for 1st, 2nd and booster vaccination, analysis of potential predictors in developing ADRs with a generalized linear mixed-effects model, analysis of TTO and TTR of ADRs and a sensitivity analysis for loss to follow-up (L2FU). RESULTS: A total of 29,837 participants completed at least the baseline and the first follow-up questionnaire for 1st and 2nd vaccination and 7,250 participants for the booster. The percentage of participants who reported at least one ADR is 74.32% (95%CI 73.82-74.81). Solicited ADRs, including injection site reactions, are very common across vaccination moments. Potential predictors for these reactions are the brand of vaccine used, the patient's age, sex and prior SARS-CoV-2 infection. The percentage of serious ADRs in the study is low for 1st and 2nd vaccination (0.24%, 95%CI 0.19--0.31) and booster (0.26%, 95%CI 0.15, 0.41). The TTO was 14 h (median) for dose 1 and slightly longer for dose 2 and booster dose. TTR is generally also within a few days. The effect of L2FU on estimations of frequency is limited. CONCLUSION: Despite some limitations due to study design and study-roll out, CEM studies can allow prompt and almost real-time observations of the safety of medications directly from a patient-centered perspective, which can play a crucial role for regulatory bodies during an emergency setting such as the COVID-19 pandemic.

Surveillance prostate biopsy utilizing piflufolastat F 18-PET/CT targeting in the intact prostate - A case report.

75-year-old patient with cochlear implant diagnosed with very low risk prostate cancer (PSA 6.44 ng/mL, and Grade Group 1 (left apical core)) managed on Active Surveillance (AS). After four years monitoring on AS, PSA was observed to increase to 10.84 and patient was reevaluated for disease progression. Due to cochlear implant, multiparametric MRI was not an imaging option and patient was referred for piflufolastat F 18-PET/CT. In addition to previously identified left sided lesion, tracer uptake was observed within the posterior transition and peripheral zone of the right lobe of the prostate, which ultimately confirmed disease progression on targeted biopsy.

Prospective Pilot Study of 18F-Fluoroestradiol PET/CT in Patients With Invasive Lobular Carcinomas.

BACKGROUND. PET/CT with 18F-fluoroestradiol (FES) (FDA-approved in 2020) depicts tissues expressing estrogen receptor (ER). Invasive lobular carcinoma (ILC) is commonly ER positive. OBJECTIVE. The primary aim of this study was to assess the frequency with which sites of histologically proven ILC have abnormal uptake on FES PET/CT. METHODS. This prospective single-center pilot study, conducted from December 2020 to August 2021, enrolled patients with histologically confirmed ILC to undergo FES PET/CT; patients optionally underwent FDG PET/CT. Two nuclear radiologists assessed FES PET/CT and FDG PET/CT studies for abnormal uptake corresponding to known ILC sites at enrollment and for additional sites of abnormal uptake, resolving differences by consensus. The primary endpoint was percentage of known ILC sites showing abnormal FES uptake. The alternative to the null hypothesis was that more than 60% of sites would have abnormal FES uptake, exceeding the percentage of ILC with abnormal FDG uptake described in prior literature. A sample size of 24 biopsied lesions was preselected to provide 81% power for the alternative hypothesis (one-sided α = .10). Findings on FES PET/CT and FDG PET/CT were summarized for additional secondary endpoints. RESULTS. The final analysis included 17 patients (mean age, 59.1 ± 13.2 years) with 25 sites of histologically confirmed ILC at enrollment (22 breast lesions, two axillary lymph nodes, one distant metastasis). FES PET/CT showed abnormal uptake in 22 of 25 (88%) lesions, sufficient to reject the null hypothesis (p = .002). Thirteen patients underwent FDG PET/CT. Four of 23 (17%) sites of histologically confirmed ILC, including additional sites detected and confirmed after enrollment, were identified with FES PET/CT only, and 1 of 23 (4%) was identified only with FDG PET/CT (p = .18). FES PET/CT depicted additional lesions not detected with standard-of-care evaluation in 4 of 17 (24%) patients (two contralateral breast cancers and two metastatic axillary lymph nodes, all with subsequent histologic confirmation). Use of FES PET/CT resulted in changes in clinical stage with respect to standard-of-care evaluation in 3 of 17 (18%) patients. CONCLUSION. The primary endpoint of the trial was met. The frequency of abnormal FES uptake among sites of histologically known ILC was found to be to be significantly greater than 60%. CLINICAL IMPACT. This pilot study shows a potential role of FES PET/CT in evaluation of patients with ILC. TRIAL REGISTRATION. ClinicalTrials.gov NCT04252859.

PET-CT in Clinical Adult Oncology: I. Hematologic Malignancies.

PET-CT is an advanced imaging modality with many oncologic applications, including staging, assessment of response to therapy, restaging and evaluation of suspected recurrence. The goal of this 6-part series of review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for the more common adult malignancies. In the first article of this series, hematologic malignancies are addressed. The classification of these malignancies will be outlined, with the disclaimer that the classification of lymphomas is constantly evolving. Critical applications, potential pitfalls, and nuances of PET-CT imaging in hematologic malignancies and imaging features of the major categories of these tumors are addressed. Issues of clinical importance that must be reported by the imaging professionals are outlined. The focus of this article is on [18F] fluorodeoxyglucose (FDG), rather that research tracers or those requiring a local cyclotron. This information will serve as a resource for the appropriate role and limitations of PET-CT in the clinical management of patients with hematological malignancy for health care professionals caring for adult patients with hematologic malignancies. It also serves as a practical guide for imaging providers, including radiologists, nuclear medicine physicians and their trainees.

PET-CT in Clinical Adult Oncology-VI. Primary Cutaneous Cancer, Sarcomas and Neuroendocrine Tumors.

PET-CT is an advanced imaging modality with many oncologic applications, including staging, therapeutic assessment, restaging and surveillance for recurrence. The goal of this series of six review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for specific oncologic indications, the potential pitfalls and nuances that characterize these applications, and guidelines for image interpretation. Tumor-specific clinical information and representative PET-CT images are provided. The current, sixth article in this series addresses PET-CT in an evaluation of aggressive cutaneous malignancies, sarcomas and neuroendocrine tumors. A discussion of the role of FDG PET for all types of tumors in these categories is beyond the scope of this review. Rather, this article focuses on the most common malignancies in adult patients encountered in clinical practice. It also focuses on Food and Drug Agency (FDA)-approved and clinically available radiopharmaceuticals rather than research tracers or those requiring a local cyclotron. This information will serve as a guide to primary providers for the appropriate role of PET-CT in managing patients with cutaneous malignancies, sarcomas and neuroendocrine tumors. The nuances of PET-CT interpretation as a practical guide for imaging providers, including radiologists, nuclear medicine physicians and their trainees, are also addressed.

PET-CT in Clinical Adult Oncology-IV. Gynecologic and Genitourinary Malignancies.

Concurrently acquired positron emission tomography and computed tomography (PET-CT) is an advanced imaging modality with diverse oncologic applications, including staging, therapeutic assessment, restaging and longitudinal surveillance. This series of six review articles focuses on providing practical information to providers and imaging professionals regarding the best use and interpretative strategies of PET-CT for oncologic indications in adult patients. In this fourth article of the series, the more common gynecological and adult genitourinary malignancies encountered in clinical practice are addressed, with an emphasis on Food and Drug Administration (FDA)-approved and clinically available radiopharmaceuticals. The advent of new FDA-approved radiopharmaceuticals for prostate cancer imaging has revolutionized PET-CT imaging in this important disease, and these are addressed in this report. However, [18F]F-fluoro-2-deoxy-d-glucose (FDG) remains the mainstay for PET-CT imaging of gynecologic and many other genitourinary malignancies. This information will serve as a guide for the appropriate role of PET-CT in the clinical management of gynecologic and genitourinary cancer patients for health care professionals caring for adult cancer patients. It also addresses the nuances and provides guidance in the accurate interpretation of FDG PET-CT in gynecological and genitourinary malignancies for imaging providers, including radiologists, nuclear medicine physicians and their trainees.

PET-CT in Clinical Adult Oncology: III. Gastrointestinal Malignancies.

PET-CT is an advanced imaging modality with many oncologic applications, including staging, assessment of response to therapy, restaging and longitudinal surveillance for recurrence. The goal of this series of six review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for specific oncologic indications, and the potential pitfalls and nuances that characterize these applications. In the third of these review articles, key tumor-specific clinical information and representative PET-CT images are provided to outline the role that PET-CT plays in the management of patients with gastrointestinal malignancies. The focus is on the use of 18F fluorodeoxyglucose (FDG), rather than on research radiopharmaceuticals under development. Many different types of gastrointestinal tumors exist, both pediatric and adult. A discussion of the role of FDG PET-CT for all of these is beyond the scope of this review. Rather, this article focuses on the most common adult gastrointestinal malignancies that may be encountered in clinical practice. The information provided here will provide information outlining the appropriate role of PET-CT in the clinical management of patients with gastrointestinal malignancies for healthcare professionals caring for adult cancer patients. It also addresses the nuances and provides interpretive guidance related to PET-CT for imaging providers, including radiologists, nuclear medicine physicians and their trainees.

PET-CT in Clinical Adult Oncology: II. Primary Thoracic and Breast Malignancies.

Positron emission tomography combined with x-ray computed tomography (PET-CT) is an advanced imaging modality with oncologic applications that include staging, therapy assessment, restaging, and surveillance. This six-part series of review articles provides practical information to providers and imaging professionals regarding the best use of PET-CT for the more common adult malignancies. The second article of this series addresses primary thoracic malignancy and breast cancer. For primary thoracic malignancy, the focus will be on lung cancer, malignant pleural mesothelioma, thymoma, and thymic carcinoma, with an emphasis on the use of FDG PET-CT. For breast cancer, the various histologic subtypes will be addressed, and will include 18F fluorodeoxyglucose (FDG), recently Food and Drug Administration (FDA)-approved 18F-fluoroestradiol (FES), and 18F sodium fluoride (NaF). The pitfalls and nuances of PET-CT in breast and primary thoracic malignancies and the imaging features that distinguish between subcategories of these tumors are addressed. This review will serve as a resource for the appropriate roles and limitations of PET-CT in the clinical management of patients with breast and primary thoracic malignancies for healthcare professionals caring for adult patients with these cancers. It also serves as a practical guide for imaging providers, including radiologists, nuclear medicine physicians, and their trainees.

PET-CT in Clinical Adult Oncology-V. Head and Neck and Neuro Oncology.

PET-CT is an advanced imaging modality with many oncologic applications, including staging, assessment of response to therapy, restaging, and longitudinal surveillance for recurrence. The goal of this series of six review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for specific oncologic indications, and the potential pitfalls and nuances that characterize these applications. In addition, key tumor-specific clinical information and representative PET-CT images are provided to outline the role that PET-CT plays in the management of oncology patients. Hundreds of different types of tumors exist, both pediatric and adult. A discussion of the role of FDG PET for all of these is beyond the scope of this review. Rather, this series of articles focuses on the most common adult malignancies that may be encountered in clinical practice. It also focuses on FDA-approved and clinically available radiopharmaceuticals, rather than research tracers or those requiring a local cyclotron. The fifth review article in this series focuses on PET-CT imaging in head and neck tumors, as well as brain tumors. Common normal variants, key anatomic features, and benign mimics of these tumors are reviewed. The goal of this review article is to provide the imaging professional with guidance in the interpretation of PET-CT for the more common head and neck malignancies and neuro oncology, and to inform the referring providers so that they can have realistic expectations of the value and limitations of PET-CT for the specific type of tumor being addressed.

Seeking an optimal dose of preoperative corticosteroids in chronic rhinosinusitis with nasal polyposis: A randomized controlled trial.

BACKGROUND: Preoperative corticosteroids have been shown to improve surgical visibility and intraoperative blood loss for chronic rhinosinusitis with nasal polyposis (CRSwNP) patients undergoing endoscopic sinus surgery (ESS). However, there is no consensus on the optimal dosing regimen. METHODS: A randomized, controlled trial was conducted to compare low, medium, and high dose corticosteroids prior to ESS. Patients with CRSwNP refractory to medical management were randomized to low (N = 8), medium (N = 10), or high (N = 5) dosing regimens of corticosteroids prior to ESS. Baseline disease severity was measured with the 22-item Sino-nasal Outcome Test and Lund-Mackay scores. Modified Lund-Kennedy endoscopic scores (MLKES) were measured at baseline and after corticosteroid treatment. Intraoperative parameters were measured including Boezaart surgical visibility score, intraoperative blood loss, and operative time. RESULTS: Medium dose corticosteroids demonstrated a superior surgical visibility score to low dose and comparable results to high dose, but these results were not significant (p = 0.33). No significant difference was observed between groups for total blood loss (p = 0.15), operative time (p = 0.87), or change in MLKES (p = 0.27). CONCLUSIONS: Current recommendations include the use of preoperative corticosteroids in patients with CRSwNP undergoing ESS, but there is no consensus on dose or duration. We did not find a statistically significant difference in surgical field visibility, intraoperative blood loss, or operative time between different dosing regimens. Further studies are needed to evaluate the efficacy of a low-dose preoperative regimen with the goal of reducing cumulative patient exposure to systemic corticosteroids.

Pineal Gland Metastasis From Gastric Carcinoid-A Rare Manifestation.

ABSTRACT: Pineal region metastases are very rare, occurring in 0.4% to 3.8% of patients with solid tumors and most frequently arise from a lung cancer primary tumor. We present a case of a 67-year-old man with a gastric well-differentiated neuroendocrine tumor (NET) metastatic to the pineal gland identified on 68Ga-DOTATATE PET/CT imaging followed by MRI confirmation. To our knowledge, this is the third NET case to be reported in the literature with such presentation and first case to be described on 68Ga-DOTATATE PET/CT. A case of metastatic bronchial NET as well as a case of metastatic esophageal NET to the pineal gland were reported previously.

An Overview of Selected Rare B-Cell Lymphoproliferative Disorders: Imaging, Histopathologic, and Clinical Features.

Lymphoproliferative disorders (LPD) are conditions characterized by the uncontrolled proliferation of B or T-cell lines. They encompass a wide spectrum of abnormalities, which may be broadly classified as reactive processes or malignant diseases, such as lymphoma, based on their cellular clonality and clinical behavior. While some of these disorders are rare, they may be encountered sporadically in clinical practice, causing diagnostic dilemmas owing to overlap in their clinical and imaging features with more common disorders. The updated 4th edition WHO classification of lymphoid neoplasms was released in 2016 to incorporate the rapid clinical, pathological, molecular biology and cytogenetic advances of some of these disorders. Despite these updates, very little information is presented in the literature from the radiology perspective. The aim of this article is to familiarize radiologists and other physicians with certain rare variants of B-cell lymphoproliferative disorders with a focus on imaging features of these disorders, as well as to provide an overview of some important updates contained within the new WHO classification of lymphoid neoplasms.

SPECT/CT in the Evaluation of Suspected Skeletal Pathology.

Dedicated multi-slice single-photon emission computed tomography/computed tomography (SPECT/CT) cameras have become widely available and are becoming a mainstay of clinical practice. The integration of SPECT and CT allow for precise anatomic location of scintigraphic findings. Fusion imaging with SPECT/CT can improve both sensitivity and specificity by reducing equivocal interpretation in comparison to planar scintigraphy or SPECT alone. This review article addresses the technique, basic science principles, and applications of integrated SPECT/CT in the evaluation of musculoskeletal pathology.

Correlation between FDG-PET uptake and survival in patients with primary brain tumors.

This study evaluates F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) semi-quantitative analysis as biomarker of tumor aggressiveness and predictor of survival in patients with primary brain tumors. Semi-quantitative analyses (SUVmax, SUVmean) were derived from FDG PET images in 78 patients with suspected recurrence of primary brain tumors based on MRI. SUVmax and the ratio of lesion SUVmax to the SUVmean of contralateral white matter (SUVmax/WM) were measured. A one-way Analysis of Variance (ANOVA), Kaplan-Meier analyses and the log rank test for evaluating statistical significance were utilized. There was statistical significance for time between FDG-PET and patient death. There was a significant difference with respect to FDG-PET time to death between patients with glioblastoma and patients with anaplastic oligodendroglioma, oligodendroglioma, and other histological subtypes. There is significant correlation with SUVmax/WM and patient survival following FDG-PET when a cut-point ratio of 1.90 is used. A 1.90 cut-point ratio of SUVmax/WM was associated with a difference in survival. GBM was associated with a significant difference in terms of reduced survival following FDG PET compared to most other histological sub-types. These results may inform current treatment and counseling strategies for patients with primary brain tumors.

Rapamycin restores brain vasculature, metabolism, and blood-brain barrier in an inflammaging model.

Rapamycin (RAPA) is found to have neuro-protective properties in various neuroinflammatory pathologies, including brain aging. With magnetic resonance imaging (MRI) techniques, we investigated the effect of RAPA in a lipopolysaccharide (LPS)-induced inflammaging model in rat brains. Rats were exposed to saline (control), or LPS alone or LPS combined with RAPA treatment (via food over 6 weeks). Arterial spin labeling (ASL) perfusion imaging was used to measure relative cerebral blood flow (rCBF). MR spectroscopy (MRS) was used to measure brain metabolite levels. Contrast-enhanced MRI (CE-MRI) was used to assess blood-brain barrier (BBB) permeability. Immunohistochemistry (IHC) was used to confirm neuroinflammation. RAPA restored NF-κB and HIF-1α to normal levels. RAPA was able to significantly restore rCBF in the cerebral cortex post-LPS exposure (p < 0.05), but not in the hippocampus. In the hippocampus, RAPA was able to restore total creatine (Cr) acutely, and N-acetyl aspartate (NAA) at 6 weeks, post-LPS. Myo-inositol (Myo-Ins) levels were found to decrease with RAPA treatment acutely post-LPS. RAPA was also able to significantly restore the BBB acutely post-LPS in both the cortex and hippocampus (p < 0.05 for both). RAPA was found to increase the percent change in BOLD signal in the cortex at 3 weeks, and in the hippocampus at 6 weeks post-LPS, compared to LPS alone. RAPA treatment also restored the neuronal and macro-vascular marker, EphB2, back to normal levels. These results indicate that RAPA may play an important therapeutic role in inhibiting neuroinflammation by normalizing brain vascularity, BBB, and some brain metabolites, and has a high translational capability.

Nuclear Medicine Education Via Instagram: A Viable Method for Informal Lifelong Learning.

Formal and informal lifelong learning allows nuclear medicine professionals to grow and change over time within this dynamic field. Over the past 2 decades, Internet-based websites have provided instantaneous access to informal learning opportunities, including nuclear medicine reference articles, videos and webinars, and case-based learning. More recently, medical educators have explored social media platforms such as Instagram, Facebook, and Twitter to provide nuclear medicine education. This article discusses the use of Instagram as a platform for lifelong learning in nuclear medicine. Several nuclear medicine Instagram sites are introduced and user characteristics and participation for a representative site are presented in an effort to learn more about this educational forum, which is increasingly being recognized among academic educators.

Protocol for a multicentre longitudinal mixed-methods study: feeding and survivorship outcomes in previously healthy young paediatric Intensive care survivors (the PIES Study).

INTRODUCTION: An admission to paediatric intensive care unit (PICU) is associated with multiple physical and environmental stressors, often involving many negative and painful oral experiences. Evidence from children with complex medical conditions suggests that feeding difficulties post-PICU stay are common, causing significant parental anxiety. Adult intensive care unit (ICU) survivor studies suggest feeding issues lasting up to 3 months post-discharge from ICU. There is, however, a paucity of evidence regarding feeding outcomes for previously healthy children following a PICU admission and whether painful oral experiences during an admission contribute to feeding difficulties post-discharge, negatively impacting on parental/caregiver anxiety. METHODS AND ANALYSIS: This longitudinal mixed-methods study will explore the impact of feeding difficulties, identifying any clinical risk factors during the first 6 months of PICU discharge in previously healthy young children (≤4 years). Parents/caregivers of children will be asked to complete questionnaires relating to: feeding difficulties, parental/caregiver stress, and child and parental/caregivers' feeding behaviours at the point of PICU discharge, 1, 3 and 6 months post-discharge. Parents/caregivers will be invited to participate in qualitative semistructured interviews at 3 and 6 months post-PICU discharge exploring parental/caregiver experiences of feeding their child after PICU. Statistical analysis of the survey data will consist of descriptive and inferential statistics, plus qualitative analysis of any free text comments using thematic analysis. ETHICS AND DISSEMINATION: This study will provide an insight and increase our understanding of the prevalence of feeding difficulties in previously healthy children admitted to PICU and parental/caregiver experiences. Multiple methods will be used to ensure that the findings are effectively disseminated to service users, clinicians, policy and academic audiences. The study has full ethical approval from the National Health Service Research Ethics Committee (Ref: 20/YH/0160) and full governance clearance.

18F-fluciclovine PET CT detection of biochemical recurrent prostate cancer at specific PSA thresholds after definitive treatment.

OBJECTIVES: To evaluate various Prostate-Specific Antigen (PSA) thresholds at which a 18F-fluciclovine PET scan could be considered in the setting of biochemical recurrent prostate cancer after definitive treatment. METHODS: We analyzed available records of men who underwent a 18F-fluciclovine PET scan after definitive therapy at a single academic institution between November 2016 to May 2018. The primary outcome was the rate of positive imaging findings at specific PSA thresholds. We then employed empiric strategies including a ROC curve and decision curve analysis to identify a specific threshold for which obtaining a positive result would be optimized. RESULTS: A total of 115 men underwent imaging with 18F-fluciclovine PET. No concerning lesions were identified in 25 (21.7%) patients, 32 (27.8%) had a solitary lesion identified, 45 (39.1%) had 2 to 5 lesions, and 13 (11.3%) had greater than 5 suspicious lesions identified. At PSA thresholds of less than 0.5, 0.5 to 2.0, and greater than 2, lesions were detected in 55.5% (12/22), 70.6% (24/34), and 91.5% (54/59) of patients respectively [P < 0.001]. Our ROC analysis yielded a PSA threshold of 2.10 while our decision curve analysis provided a PSA cutoff of 1.38. CONCLUSION: This study constitutes an early single institution series evaluating the use of 18F-fluciclovine PET scans in the assessment of biochemically recurrent prostate cancer after definitive treatment. The probability of having positive imaging findings and increasing numbers of suspicious lesions rises with increasing PSA. Utilization of a lower PSA threshold of 0.5 may allow earlier intervention with salvage therapies in biochemical recurrence. However, using a threshold below 1 carries a higher risk of negative scans. Employing a higher PSA threshold of 1 to 2 carries greater sensitivity and specificity and may maximize identifying individuals with early BCR who may benefit from early intervention, while minimizing negative scans.