Establishing Normal Testicular ¹⁸F-FDG PET/CT SUVs

Area of Science:

• Nuclear Medicine
• Radiology
• Oncology

Background:

• Accurate interpretation of 18F-FDG PET/CT scans requires knowledge of normal testicular standardized uptake values (SUVs).
• Establishing these normal ranges is crucial for differentiating physiological uptake from pathological processes in the testicles.

Purpose of the Study:

• To determine and report normal testicular SUV ranges in adult men within North America.
• To provide a reference for clinicians interpreting testicular FDG uptake on PET/CT scans.

Main Methods:

• Retrospective analysis of FDG PET/CT examinations from 350 adult male patients.
• Review of 700 testicles, collecting SUVmax, SUVmean, and visual uptake patterns.
• Statistical analysis of SUV values across different age groups.

Main Results:

• Testicular SUVmean and SUVmax values were documented for various age groups, showing a peak in the 4th decade.
• A statistically significant decline in testicular SUVs was observed with increasing age (p ≤ .001).
• A minor negative correlation was found between blood glucose levels and testicular SUVmean (r = -0.12).

Conclusions:

• This study presents the largest cohort to date for normal testicular SUVs on FDG PET/CT.
• The established ranges can guide clinical interpretation of testicular FDG activity.
• Potential discrepancies in SUV values may arise from variations in patient demographics and PET technology.