Of the 5 WDL/DDL negative for MDM2 amplification, 4 had final diagnosis revised (2 presumed DDL revised to spindle cell sarcoma not otherwise specified (NOS), and 2 WDL revised to lipomas), while 1 (which was retroperitoneal, with adjacent unequivocal WDL components) had its histologic diagnosis of DDL retained. The gene discussed is MDM2; the disease is spindle cell sarcoma.