From the Research Division, Peter MacCallum Cancer Centre (Dr. Thomas); Sarcoma Unit, Department of Surgery, National Cancer Institute, Milan, Italy (Dr. Gronchi); Sarcoma Site Group, Department of Radiation Oncology, University of Toronto, Princess Margaret Hospital (Dr. O'Sullivan)
Authors disclosures of potential conflicts of interest are found at the end of this article.
Address reprint requests to David M. Thomas, MD, Peter MacCallum Cancer Centre, St Andrew's PL, East Melbourne, Victoria 3002, Australia; e-mail: david.thomas{at}petermac.org
Overview: Retroperitoneal sarcomas are complex, heterogeneous cancers requiring expert multidisciplinary care. The most common types of retroperitoneal sarcoma are liposarcomas and leiomyosarcomas. Well- and dedifferentiated liposarcoma in particular are driven by highly focal amplification events, resulting in over-expression of MDM2 and cyclin-dependent kinase 4 (CDK4). Surgery is critical to treatment of the disease and requires an aggressive approach, including multivisceral resection. Even in advanced disease, surgery may provide useful palliation for patients with slow-growing disease. Radiotherapy (RT) has a definite role in reducing relapse, although prospective trials of adjuvant or neoadjuvant RT specifically for retroperitoneal sarcomas must be undertaken. Chemotherapy has a limited role in the adjuvant setting for most forms of retroperitoneal sarcoma but has an increasing role in advanced disease. Novel therapeutic agents that target MDM2 and CDK4 offer promise for subsets of these diseases.