Feasibility of whole-body MRI for detecting metastatic myxoid liposarcoma: a case series

No feasible method currently exists to evaluate systemic metastasis in patients with myxoid liposarcoma. The purpose of this study was to determine the feasibility of performing whole-body magnetic resonance imaging (MRI) to detect metastatic myxoid liposarcoma. From June 2008 to May 2010, all patients who were newly diagnosed with myxoid liposarcomas at our institution underwent whole-body MRI along with other conventional imaging methods. We divided the whole body into 38 sections (7 soft tissue sections and 31 bone tissue sections). In total, there were 570 regions (105 soft tissue regions and 465 bony regions) in 15 patients (10 men and 5 women) who underwent whole-body MRI.Of 105 soft tissue regions, there were 4 true positives, 3 false positives, 1 false negative, and 97 true positives. Of 465 bone tissue regions, there were 11 true positives, 5 false positives, 2 false negatives, and 447 true negatives. In soft tissue, whole-body MRI for the detection of metastatic lesion showed a sensitivity of 80%, a specificity of 97.0%, a positive predictive value of 57.1%, and a negative predictive value of 99.0%. In bone tissue, whole-body MRI had a sensitivity of 84.6%, a specificity of 98.9%, a positive predictive value of 68.8%, and a negative predictive value of 99.6%.Whole-body MRI is feasible and effective for detecting bone and soft tissue metastasis in patients with myxoid liposarcoma.