Standardized Uptake Value from Semiquantitative Bone Single-Photon Emission Computed Tomography/Computed Tomography in Normal Thoracic and Lumbar Vertebrae of Breast Cancer Patients

STUDY DESIGN: Retrospective study. PURPOSE: This study aims to semiquantitatively evaluate the standardized uptake value (SUV) of (99m)Tc-methylene diphosphonate (MDP) radionuclide tracer in the normal vertebrae of breast cancer patients using an integrated single-photon emission computed tomography (SPECT)/computed tomography (CT) scanner. OVERVIEW OF LITERATURE: Molecular imaging techniques using gamma cameras and stand-alone SPECT have traditionally been utilized to evaluate metastatic bone diseases. However, these methods lack quantitative analysis capabilities, impeding accurate uptake characterization. METHODS: A total of 30 randomly selected female breast cancer patients were enrolled in this study. The SUV mean (SUV(mean)) and SUV maximum (SUV(max)) values for 286 normal vertebrae at the thoracic and lumbar levels were calculated based on the patients’ body weight (BW), body surface area (BSA), and lean body mass (LBM). Additionally, 106 degenerative joint disease (DJD) lesions of the spine were also characterized, and both their BW SUV(mean) and SUV(max) values were obtained. A receiver operating characteristic (ROC) curve analysis was then performed to determine the cutoff value of SUV for differentiating DJD from normal vertebrae. RESULTS: The mean±standard deviations for the SUV(mean) and SUV(max) in the normal vertebrae displayed a relatively wide variability: 3.92±0.27 and 6.51±0.72 for BW, 1.05±0.07 and 1.75±0.17 for BSA, and 2.70±0.19 and 4.50±0.44 for LBM, respectively. Generally, the SUV(mean) had a lower coefficient of variation than the SUV(max). For DJD, the mean±standard deviation for the BW SUV(mean) and SUV(max) was 5.26±3.24 and 7.50±4.34, respectively. Based on the ROC curve, no optimal cutoff value was found to differentiate DJD from normal vertebrae. CONCLUSIONS: In this study, the SUV of (99m)Tc-MDP was successfully determined using SPECT/CT. This research provides an approach that could potentially aid in the clinical quantification of radionuclide uptake in normal vertebrae for the management of breast cancer patients.