An International Survey Investigating the Incidence and Management of Brown Fat Uptake on 18F-FDG PET/CT at Children's Hospitals and Interventions for Mitigation.

Brown fat can present challenges in patients with cancer who undergo 18F-FDG PET scans. Uptake of 18F-FDG by brown fat can obscure or appear similar to active oncologic lesions, causing clinical challenges in PET interpretation. Small, retrospective studies have reported environmental and pharmacologic interventions for suppressing brown fat uptake on PET; however, there is no clear consensus on best practices. We sought to characterize practice patterns for strategies to mitigate brown fat uptake of 18F-FDG during PET scanning. Methods: A survey was developed and distributed via e-mail LISTSERV to members of the Children's Oncology Group diagnostic imaging committee, the Society for Nuclear Medicine and Molecular Imaging pediatric imaging council, and the Society of Chiefs of Radiology at Children's Hospitals between April 2022 and February 2023. Responses were stored anonymously in REDCap, aggregated, and summarized using descriptive statistics. Results: Fifty-five complete responses were submitted: 51 (93%) faculty and fellow-level physicians, 2 (4%) technologists, and 2 (4%) respondents not reporting their rank. There were 43 unique institutions represented, including 5 (12%) outside the United States. Thirty-eight of 41 (93%) institutions that responded on environmental interventions reported using warm blankets in the infusion and scanning rooms. Less than a third (n = 13, 30%) of institutions reported use of a pharmacologic intervention, with propranolol (n = 5, 38%) being most common, followed by fentanyl (n = 4, 31%), diazepam (n = 2, 15%), and diazepam plus propranolol (n = 2, 15%). Selection criteria for pharmacologic intervention varied, with the most common criterion being brown fat uptake on a prior scan (n = 6, 45%). Conclusion: Clinical practices to mitigate brown fat uptake on pediatric 18F-FDG PET vary widely. Simple environmental interventions including warm blankets or increasing the temperature of the injection and scanning rooms were not universally reported. Less than a third of institutions use pharmacologic agents for brown fat mitigation.

Implementation of an Anterior Mediastinal Mass Pathway to Improve Time to Biopsy and Multidisciplinary Communication.

Background: Mediastinal masses in children with cancer present unique challenges, including the risk of respiratory and hemodynamic compromise due to the complex anatomy of the mediastinum. Multidisciplinary communication is often a challenge in the management of these patients. After a series of patients with mediastinal masses were admitted to Riley Hospital for Children Pediatric Intensive Care Unit, the time from presentation to biopsy and pathology was greater than expected. We aimed to reduce the time to biopsy by 25% and demonstrate improved multidisciplinary communication within 6 months of protocol implementation for patients presenting to Riley Hospital for Children Emergency Department with an anterior mediastinal mass. Methods: Quality improvement methodology created a pathway that included early multidisciplinary communication. The pathway includes communication between the emergency department and multiple surgical and medical teams via a HIPPA-compliant texting platform. Based on patient stability, imaging findings, and sedation risks, the approach and timing of the biopsy were determined. Results: The pathway has been used 20 times to date. We successfully reduced the time to biopsy by 38%, from 25.1 hours to 15.4 hours. There was no statistically significant reduction in time to pathology. The multidisciplinary team reported improved communication from a baseline Likert score of 3.24 to 4. Conclusions: By initiating early multidisciplinary communication, we reduced the time to biopsy and pathology results, improving care for our patients presenting with anterior mediastinal masses.