MUSCULOSKELETAL TUMORS - DOES FAST DYNAMIC CONTRAST-ENHANCED SUBTRACTION MR-IMAGING CONTRIBUTE TO THE CHARACTERIZATION

PURPOSE: To prospectively analyze the value of fast, dynamic, subtract ion magnetic resonance (MR) imaging in the characterization of musculo skeletal tumors MATERIALS AND METHODS: In 175 consecutive patients wit h a musculoskeletal mass, dynamic contrast-enhanced subtraction MR ima ging was performed after administration of 0.1 mmol per kilogram of bo dy weight gadopentetate dimeglumine or gadoteridol. A turbo gradient-e cho technique was used with a temporal resolution 1-3 seconds. The int erval between arterial and early tumor enhancement pattern (peripheral or diffuse) of enhancement, and the progression of tumor enhancement, as visualized on time-signal intensity curves, were assessed. MR enha ncement features were related to the histopathologic diagnoses. RESULT S: Differentiation of benign from malignant soft-tissue masses was pos sible with a sensitivity of 91% based on start of enhancement, a sensi tivity of 73% and specificity of 97% based on peripheral or diffuse en hancement, and a sensitivity of 86% and specificity of 81% based on pr ogression of enhancement. Benign bone tumors could not be accurately d ifferentiated from malignant bone tumors on the basis of the three def ined parameters (sensitivity, 63%-76%; specificity, 50%-76%). CONCLUSI ON: Dynamic, contrast-enhanced, subtraction MR images may be useful to differentiate malignant from benign soft-tissue masses.