Repeatability of SUV in Oncologic ¹⁸F-FDG PET

Area of Science:

• Nuclear Medicine
• Oncology
• Medical Imaging

Background:

• Quantitative analysis in 18F-FDG PET enhances accuracy for tumor response assessment.
• Standardized Uptake Value (SUV) is the primary metric for tumor quantification, despite limitations.
• Early prediction of tumor response using pre- and post-treatment SUV differences is increasingly studied.

Purpose of the Study:

• To review and compare data on SUV repeatability in 18F-FDG PET.
• To address methodological variations in test-retest studies for SUV.
• To establish reliable margins for interpreting SUV changes in treatment response.

Main Methods:

• Review of multiple test-retest studies on SUV repeatability.
• Analysis of various repeatability metrics, relative units, log transformation, and asymmetric limits.
• Assessment of within-subject coefficient of variation for tumor SUV.

Main Results:

• Tumor SUV exhibits a within-subject coefficient of variation of approximately 10% with careful protocol adherence.
• SUV reductions >25% or increases >33% are unlikely to stem from measurement variability.
• Broader margins may be necessary for sites with less stringent protocol compliance.

Conclusions:

• Standardized Uptake Value (SUV) is a highly repeatable imaging biomarker.
• SUV is well-suited for monitoring tumor treatment response in individual patients.
• Understanding SUV repeatability is essential for accurate quantitative analysis in 18F-FDG PET.