COMPARISON OF TECHNETIUM-99M-MIBI AND TECHNETIUM-99M-TETROFOSMIN UPTAKE BY MUSCULOSKELETAL SARCOMAS

Technetium-99m-MIBI was initially developed for heart studies but it c an also be used to depict tumors, predict multidrug resistance and eva luate chemotherapy. Recently, Tc-99m-tetrofosmin, which exhibits simil ar physical properties, has been launched for heart studies. Tumor upt ake and prediction of multidrug resistance have also been reported reg arding the latter tracer. A comparison of these two tracers regarding the detectability of musculoskeletal sarcoma has been made. Methods: T wenty patients with musculoskeletal sarcoma of the extremities or pelv is underwent planar examination after the administration of Tc-99m-MIB I and Tc-99m-tetrofosmin with an interval of 2-7 days. The tumor activ ity was compared with one ipsilateral and one contralateral background region. Results: There was a small, but not significant, difference i n favor of Tc-99m-MIBI with regard to both background regions. Conclus ion: Technetium-99m-MIBI and Tc-99m-tetrofosmin can both be used to vi sualize musculoskeletal sarcomas. The choice may depend on which agent is used routinely for myocardial studies in the laboratory.