[Preliminary application of 99Tc(m)-MIBI scintigraphy for judgment of bone malignant and benign lesions]

The aim of this study was to assess the value of Tc-99m-hexakis-2-methoxyisobutylisonitrile (MIBI) scintigraphy diagnosing the malignant and benign bone lesions in comparison with a conventional bone tracer 99Tm-methylene-diphosphonate (MDP).

99Tc(m)-MDP three-phase bone scintigraphy and 99Tc(m)-MIBI dynamic and quiet states scintigraphy were obtained from 39 patients with proved malignant diseases or suspected bone metastases after bolus injected intravenously radiopharmaceuticals, respectively. The results were compared with using film reading and regions of interesting (ROI) technique.

139 bone metastases were confirmed in 169 lesions. The sensitivity of 99Tc(m)-MDP or 99Tc(m)-MIBI scintigraphy was 90.3% or 68.4% (P < 0.05), respectively; the specificity was 33.3% or 96.7% (P < 0.05), respectively;the false positive rate was 6.71% or 1.04%. No statistical difference was appeared in both malignant tumors and benign lesions with 99Tc(m)-MDP scintigraphy. However, while with 99Tc(m)-MIBI scintigraphy, there were significant statistical difference (P < 0.05) both in malignant tumors and benign lesions. 99Tc(m)-MIBI scintigraphy could early detect 17 bone metastases and proved 11 lesions to be benign bone foci and 2 to be pathologic bone fractures.

Although 99Tc(m)-MIBI scintigraphy has lower general sensitivity than 99Tc(m)-MDP scintigraphy, it has higher specificity, lower false positive rate and can detect lesions early and judge the quality, which may be helpful in the evaluation and strategy of clinical therapy for bone metastases.