The molecular signatures of mediastinal liposarcomas correspond to those of liposarcomas elsewhere, with presence of the t(12;16) FUS-DDIT-3 fusion in myxoid liposarcoma [107] and amplification of mdm-2 in well-differentiated and dedifferentiated liposarcoma [101, 108]. The gene discussed is MDM2; the disease is myxoid liposarcoma.