Medical management of unresectable, recurrent low-grade retroperitoneal liposarcoma: integration of cytotoxic and non-cytotoxic therapies into multimodality care.

Liposarcomas of the retroperitoneum are rare tumors, and best managed by an expert multidisciplinary team consisting of a surgical oncologist with appropriate medical oncology and radiation oncology collaboration. For large tumors, surgical excision with wide margins is difficult to achieve, and even wide margins cannot ensure that microscopic remnants of residual disease will not grow back in the future. For these reasons, even following expert resection, local recurrence is common. For patients with recurrent and unresectable liposarcoma, treating the sarcoma while maintaining quality of life becomes the major therapeutic goal. Importantly, patients with advanced recurrent disease demonstrate the need for multidisciplinary team involvement, with timely consideration of palliative surgical, radiation therapy, and chemotherapy options. Such patients also represent ideal candidates for investigational approaches aimed at identifying new agents with which to treat this disease. In addition to the development of new cytotoxic agents, patients may be candidates for novel strategies such as differentiation therapies or anti-angiogenic approaches. The recent explosion of knowledge regarding the cytogenetics, molecular, and cellular biology of liposarcomas allows us to remain positive that new translational therapies will be developed to improve the clinical outcomes of patients with these diseases. Current strategies, such as the use of PPARgamma ligands to differentiate liposarcomas, will soon be tested in major national collaborative trials, and the cooperation of surgeons and medical oncologists at all levels of community and academic practice will be crucial to obtain answers in this field. This review will summarize an illustrative case in the process of describing the natural history and potential interventions which should be considered for patients with this disease.