Liposarcoma is a tumor that arises from fat tissue. This tumor often occurs in the thigh, legs, behind the knee or in the abdomen, but it can be found in other parts of the body, in the retroperitoneum, and, less often, in the head and neck area. Their primary occurrence in the skin is rare. Because a liposarcoma may grow into surrounding tissues or organs, it is considered a malignant tumor. The World Health Organization classification of soft tissue tumors recognizes 5 types of liposarcomas: well differentiated (which includes the adipocytic, sclerosing, and inflammatory subtypes), dedifferentiated, myxoid, round cell and pleomorphic.
Most patients with liposarcoma have no symptoms until the tumor is large and invades the neighboring organs or tissues, causing tenderness, pain or functional problems. Although surgical removal of the tumor is the curative treatment, some patients may benefit from chemotherapy and radiation.
Liposarcomas are not common tumors, and when they do occur, it’s usually in adults ages 50 – 65.
Injury and lifestyle factors such as smoking, diet and exercise are not linked to the risk for soft tissue sarcoma. An injured area may swell and resemble a tumor, but your doctor can use imaging to rule out a sarcoma.
Radiation exposure accounts for less than 5% of sarcomas. But patients might develop sarcomas from radiation given to treat other cancers, like breast cancer or lymphoma. The sarcoma often starts in the part of the body that was treated with radiation. The average time between the radiation treatments and the diagnosis of a sarcoma is about 10 years.
Some family cancer syndromes increase a person's risk of developing soft tissue sarcomas.