Evaluation of soft tissue sarcomas response to preoperative treatment: Assessment by angiography, thallium scintigraphy, and dynamic MRI

Background: Assessment of the response of soft tissue sarcomas to preoperative treatment is of significant clinical importance. However, there are few reports concerning the accuracy of each imaging technique in assessing the response of soft tissue sarcomas to preoperative treatment. Methods: The responses of 15 soft tissue sarcomas to preoperative treatment by digital subtraction angiography, thallium scintigraphy, and dynamic magnetic resonance imaging (MRI) were compared with histologic evaluation of the resected specimens. Tumors with at least 90% histologic necrosis were considered to be effectively treated. Results: The accuracy of each assessment technique was 58.3% for digital subtraction angiography, 80% for thallium scintigraphy, and 77.8% for dynamic MRI. Both the differences in slope before and after treatment and the posttreatment slope values of dynamic MRI correlated with the histologic responses. Conclusion: Thallium scintigraphy and dynamic MRI showed sufficient value in the assessment of soft tissue sarcomas responses to preoperative treatment. Dynamic MRI had major advantages in its quantitative and spatial resolutions.