Atypical lipomatous tumor: Molecular characterization

Purpose of review: Atypical lipomatous tumors/well-differentiated liposarcomas (ALT/WDLs) are one of the more frequent mesenchymal neoplasms and are characterized by specific chromosome aberrations: supernumerary chromosome or giant marker chromosome or both. Extra copies of known oncogenes such as MDM2, CDK4, SAS, HMGA2 and others are present in this abnormal genetic material. Recent findings: In the past few years, several papers have further dissected the genetic alterations present in these tumors, allowing the identification of new potential oncogenes. Summary: ALT/WDLs represent therefore an interesting model for assessing the potential role of these oncogenes, not only in the pathogenesis, but also as a therapeutic target.