Liposarcoma occurs in the deep soft tissue of extremities and in the retroperitoneum. It is the most common soft tissue sarcoma and accounts for 20% of all mesenchymal tumors. They are typically large bulky tumors which tend to have multiple satellite lesions extending beyond the gross confines of the tumor. Patients usually note a deep seated mass in their soft tissue for tumors of the extremity. Only when the tumor is very large, do symptoms of pain or functional disturbances occur. Retroperitoneal tumors may present with signs of weight loss and emaciation and abdominal pain. These tumors may also compress the kidney or ureter leading to kidney failure.
Histological patterns vary from round cell, myxoid, well differentiated, and pleomorphic type. The round cell and pleomorphic types are the most aggressive with a relentless history of recurrences. The pathologist must differentiate this tumor from other soft tissue sarcomas, particularly malignant fibrous histiocytomas.
Soft tissue sarcomas occur in approximately 5000 patients in the United States per year. Overall, liposarcomas account for less than 20% of all soft tissue sarcomas, and the average patient age at presentation is 50 years. However, in children, liposarcomas account for less than 5% of all soft tissue sarcomas; fewer than 60 cases in children have been reported.
Surgery is the mainstay of treatment for most soft tissue sarcomas, particularly for liposarcoma in children, which tends to be locally aggressive. Surgery includes biopsy of surgical removal of the entire tumor. It is especially important for surgeons to remove wide margins of surrounding healthy tissue, to ensure there are no remaining cancer cells. In cases where the tumor is found in the extremities, it may be necessary to remove all or part of the limb. In most cases limb-sparing surgery is used to avoid amputation.