Differences in Suvmax Spect/ct Bone Scan Between Bone Metastatic Lesions and Non-metastatic Lesions in Breast Cancer Patients

Background Breast cancer is the most common cancer among women in Indonesia. Approximately 65–75% breast cancer cases have spread to the bone. Early detection of bone metastases is crucial for determining patient management strategies. Bone metastatic lesions in breast cancer are typically osteolytic, but invasion into bone tissue will still stimulate an osteoblastic response. This osteoblastic activity can be visualized using ^99m Tc-MDP SPECT/CT bone scan. Quantitative parameters, such as SUVmax, are used to strengthen a qualitative interpretation visually and have the potential to differentiate between metastatic and non-metastatic bone lesions objectively. This study aimed to evaluate the accuracy of SUVmax from SPECT/CT bone scan in differentiating bone metastatic lesions from non-metastatic lesions in breast cancer patients. Methods This retrospective study was conducted on breast cancer patients who underwent bone scan and SPECT/CT at Dr. Hasan Sadikin General Hospital from May 2024 to June 2025. SUVmax was obtained by determining the volume of interest (VOI) based on fused SPECT/CT images. Statistical analysis used a Mann–Whitney to compare SUVmax between groups and ROC curve analysis to assess threshold value, sensitivity, specificity, and accuracy. Results A total of 182 SPECT/CT bone scan lesions from 62 subjects with breast cancer, consisting of 134 metastatic and 48 non-metastatic lesions, were analyzed in this study. The SUVmax in the metastatic group was (28.60 ± 11.40) g/mL, significantly higher than in the non-metastatic group (10.10 ± 3.65) g/mL ( p < 0.001 ) . ROC analysis showed an optimal SUVmax cutoff 16.7 g/mL, with an AUC of 0.964. Based on this cut-off, sensitivity, specificity, PPV, NPV, and accuracy were 92.48%, 94.55%, 99%, 82%, and 94% respectively. Conclusion Metastatic lesions had significantly higher SUVmax than non-metastatic lesions. SUVmax can be used as a quantitative parameter to support the diagnosis of bone metastases in breast cancer patients.