99mTc-Exametazime as a Breast Tumor-Seeking Agent: Comparison with 99mTc-Sestamibi

Journal of Nuclear Medicine

Hans Jacobsson¹  Rimma Danielsson¹  Brigitte Wilczek¹  Fuat Celebiouglu¹  Stig A. Larsson¹  Leif Svensson¹ 

关键词: breast cancer;    chemotherapy resistance;    mammoscintigraphy;    ^99mTc-exametazime;    ^99mTc-sestamibi;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

99mTc-Sestamibi is commonly used for mammoscintigraphy. Occasional uptake of 99mTc-exametazime in various tumors has been described. In this study, an intraindividual comparison of these 2 radiopharmaceuticals for mammoscintigraphy was made. Methods: A kinetic study (30 min) in the lateral prone view of 20 breast tumors (≥1 cm) in 20 women was conducted with 99mTc-exametazime. Thereafter, 21 breast tumors (≥1 cm) in 21 women were examined with both agents (2 patients were included in both groups) under identical conditions (interval, 2–7 d). In the latter group, the tumor-to-background breast activity ratio and the tumor uptake normalized to the administered activity (cps/MBq) at 10 min after injection were calculated and compared for both agents. Results: All tumors (43 tumors in 39 patients) were visualized with 99mTc-exametazime. There was also one instance of false-positive uptake using this agent. The uptake phase lasted ∼10 min. Thereafter, the activity was practically stable. 99mTc-Sestamibi failed to depict 4 tumors. On the group level, the tracers did not differ in tumor-to-background activity ratio or normalized tumor uptake. Intraindividual agreement in tumor-to-background ratios between the tracers was moderate (intraclass correlation coefficient = 0.49). Conclusion: Uptake of 99mTc-exametazime in breast tumors ≥ 1 cm seems to be comparable with that of 99mTc-sestamibi at a group level. The specificity is unknown. There is a restricted intraindividual agreement between the tracers, confirming different uptake mechanisms. This may open up possibilities for assessing different tumor characteristics in vivo, especially since the uptake of both agents is based on mechanisms believed to be involved in resistance to antineoplastic drugs.

【 授权许可】

Unknown