Technetium-99m-MIBI Uptake in Bone Metastases A Comparative Study With Technetium-99m-MDP

摘要

Aim:The purpose of this study was to determine the potential of Tc-99m hexakis-2-methoxyisobutyliso-nitrile (MIBI) for detection of bone metastases in breast cancer patients in comparison to Tc-99m methylene diphosphonate (MDP) bone scans.Materials and Methods:Tc-99m MIBI and Tc-99m MDP scans were performed in 55 patients with breast cancer and suspected bone metastases. Three to four hours following i.v. injection of 740 MBq (20 mCi) Tc-99m MDP, a total-body study was performed. Spot images of abnormal areas were also taken. Tc-99m MIBI scanning was performed within the same week of obtaining the Tc-99m MDP scans. Acquisition of the Tc-99m MIBI images was begun 1 minute after bolus injection of Tc-99m MIBI. First, lumbar spine and then spot images of pelvis, thorax, and head were acquired for 5 minutes. Following spot images whole-body anterior and posterior images were also obtained.Results:Conventional Tc-99m MDP bone scans showed abnormal skeletal uptake in 276 lesions. Tc-99m MIBI scans showed abnormal skeletal uptake in 120 lesions. Bone metastases were confirmed in 149 lesions by plain radiography, CT, MRI, marrow cytology, or evidence of progressive bone lesions on follow-up Tc-99m MDP. Although all of the metastatic lesions (n: 149) were detected on Tc-99m MDP scans, 120 lesions of the metastatic lesions (120/149 = 80%) were detected on Tc-99m MIBI scans. On the other hand, false-positive findings on Tc-99m MDP scans were quite high; 127 lesions of the 276 lesions were false-positive (127/276 = 46%). There were no false-positive results on Tc-99m MIBI scans.Conclusion:In our study, it has been shown that Tc-99m MIBI scans have relative comparable sensitivity to Tc-99m MDP scans (80% and 100%, respectively) in detect-ing bone metastases in patients with breast cancer. If we consider the excellent specificity of Tc-99m MIBI scans compared with Tc-99m MDP bone scans, we can conclude that Tc-99m MIBI scans have a very important complementary role in detecting bone metastases.