Liposarcoma.

Liposarcoma is second in frequency only to malignant fibrous histiocytoma among the soft-tissue sarcomas. It occurs almost exclusively in adults and is found most often in the thigh or retroperitoneum. It rarely arises from a lipoma and does not occur in the subcutaneous tissues. Liposarcomas are divided into histologic subtypes with different microscopic appearances and slightly different behavior characteristics. Surgical resection with a wide surgical margin is the treatment of choice. When amputation is required to obtain an adequate surgical margin, local irradiation can be used as an adjuvant and a limb-sparing operation can be done. Currently, no evidence exists that adjuvant chemotherapy is indicated for patients with liposarcoma, although numerous studies are being done to investigate its use. As is the case for all sarcomas, the lung is the most common site of metastasis; however, liposarcoma has an unusual propensity to metastasize to the retroperitoneum, mediastinum, and bone.