Normal Skeletal Standardized Uptake Values Obtained from Quantitative Single-Photon Emission Computed...

Area of Science:

• Nuclear Medicine
• Oncology
• Radiopharmacology

Background:

• Quantitative imaging in breast cancer diagnostics is crucial for monitoring treatment response.
• Tc-99m methylene-diphosphonate (MDP) scintigraphy is widely used for skeletal imaging.
• Establishing normal uptake values is essential for accurate interpretation of quantitative SPECT/CT studies.

Purpose of the Study:

• To determine the standard uptake values (SUVs) of Tc-99m MDP in normal skeletal sites of breast cancer patients.
• To assess the influence of different post-injection acquisition times on these SUVs.
• To provide reference ranges for quantitative analysis in breast cancer follow-up.

Main Methods:

• Sixty breast cancer patients undergoing Tc-99m MDP SPECT/CT were analyzed.
• Patients were grouped based on acquisition time: 2, 3, 4, and 5 hours post-injection.
• Quantitative analysis (SUVmax, SUVmean) was performed using Q.Metrix software on defined skeletal regions of interest.

Main Results:

• Highest normal SUVmax and SUVmean values were observed in lumbar/thoracic vertebrae and pelvis across all time groups.
• Lowest normal SUVmax and SUVmean values were found in the humerus and ribs.
• Significant time-dependent differences (P < 0.05) in SUVmax and SUVmean were noted for various skeletal sites.

Conclusions:

• Normal SUV values for Tc-99m MDP in breast cancer patients exhibit significant variability across different skeletal sites.
• Vertebral bodies and the pelvis demonstrate the highest normal SUV values.
• The time-dependent nature of SUVs highlights the importance of consistent imaging timing for serial follow-up studies.