Tc-99m Tetrofosmin imaging for viability assessment in osseous and soft tissue sarcomas in response to chemotherapy: blood pool or retention index?

ABSTRACT

The aim of the work was to evaluate the role of Tc-99m tetrofosmin in the assessment of the response of bone and soft tissue sarcomas to chemotherapy. In this study, 14 cases with histologically-proved osseous and soft tissue sarcomas were evaluated using Tc-99m tetrofosmin as an indicator of viable tumors for the assessment of chemotherapeutic induced response. Scanning was done at 10 minutes and 30 minutes after radiopharmaceutical injection with the calculation of tumor to non-tumor uptake ratios and retention indices. A significant correlation was found between the prechemotherapy 30 minutes tumor to non-tumor uptake ratio and the retention index of Tc-99m tetrofosmin as compared with the standard histologic grading of the chemotherapeutic effect. Moreover, post chemotherapy 10 minutes tumor to non-tumor uptake ratio was significantly correlated to such histologic grading. It was concluded that Tc-99m tetrofosmin is a good predictor of the tumor response to chemotherapy in osseous and soft tissue sarcomas