Standardization in pre-imaging protocols in follow up 18FDG-PET/CT studies in lymphoma patients; reasons beyond benchmark

Standardization of follow-up 18FDG-PET/CT studies

Abstract

Background: The standardization is necessary for the utilization of quantitative ¹⁸FDG-PET/CT as an imaging biomarker. Routine assessment by regular clinical audits of facilities performing ¹⁸FDG -PET/CT are crucial for ensuring compliance with standardized pre-imaging protocols and minimizing deviations from established benchmarks.

Objectives: Assessment of the compliance with standardized pre-imaging protocols for follow-up ¹⁸FDG-PET/CT studies in lymphoma patients and to determine the deviation(s) beyond established benchmarks.

Material and Methods: This is a retrospective study that was conducted at PET/CT section of Radiology department and duly exempted from review by the ethical review committee in February-2023. The 52 lymphoma patients had undergone baseline and interim ¹⁸FDG-PET/CT from timeframe of 2021-2022 were included. The demographics and pre-imaging protocols, including the ¹⁸FDG dose, hepatic SUVmean (Standardized uptake value) and uptake time were retrieved. The compliance of standardized imaging protocol in the follow-up ¹⁸FDG-PET/CT was calculated against 85% benchmark as one of the key performance indicators (KPIs) in the department of set for JCIA (Joint Commission International Accreditation) standards.  Any significant deviations in compliance from KPI were analyzed.  

 Results: In follow-up ¹⁸FDG PET/CT studies, no significant differences were observed in demographic and pre-imaging parameters. The compliance rates for ¹⁸FDG dose and hepatic SUVmean were 86%, surpassing the 85% benchmark as per institutional KPI. Conversely, there was a deficiency in adherence to the institutional benchmark for uptake time, with a compliance of 80% compared to the required 85%.

Conclusion: The study findings indicate commendable adherence to standardization in pre-imaging protocols of ¹⁸FDG dose and hepatic SUVmean for serial ¹⁸FDG PET/CT examinations in accordance with international and institutional benchmarks. However, sub-standardization in compliance was observed in uptake time between ¹⁸FDG injection and scanning beyond institutional KPI, especially delays associated with the positioning of bed-bound and unplanned prolonged radiation planning patients.

Key Words: ¹⁸FDG-PET/CT, follow-up, Standardization, pre-imaging, benchmark