A myxoid liposarcoma is a rare type of cancer which develops from fat cells and which may cause no symptoms, appearing as a painless lump which slowly increases in size. Occasionally, the tumor may quickly enlarge and could become ulcerated. Often, symptoms are only experienced when the cancer has become big enough to press against surrounding structures. As a result, pain and numbness may occur, and sometimes loss of movement. More general symptoms of tiredness, weight loss, nausea and vomiting may also be experienced.
Soft tissue sarcomas grow from cells within the body's connective tissue. Inside the body, connective tissue forms a soft framework which connects, protects and supports organs and other tissues. Liposarcomas are the most commonly found soft tissue sarcomas in adults. They happen to develop from fat cells, but other types of soft tissue sarcoma may arise from different cells inside connective tissue. Five types of liposarcoma have been identified and these are known as well-differentiated, dedifferentiated, myxoid, pleomorphic and round cell liposarcoma.
Myxoid liposarcomas tend to occur more frequently in the limbs and, at first, their slow growth may go unnoticed. The swelling may only be drawn to a person's attention if it becomes painful, perhaps after it has been accidentally knocked or scraped, or if it has become very large. Sometimes, a myxoid liposarcoma growing on a limb may be tender or painful, and growth may be rapid in some cases. Any lump bigger than 2 inches (about 5 cm) or which is continuing to enlarge should be seen by a doctor, as should a painful swelling or one which appears to be attached to tissue deeper than the skin.
If a myxoid liposarcoma develops inside the abdominal cavity, it will not be visible and may increase to around a few pounds, or a couple of kilos, in weight before causing obvious symptoms. Vomiting, nausea, abdominal pain and swelling may occur. If the tumor presses on a nerve, this can lead to symptoms of numbness and, if it interferes with a muscle, a body part may stop functioning normally. When a myxoid liposarcoma presses on blood vessels the circulation may become obstructed, and back pressure could lead to visibly swollen veins.
The treatment of a myxoid liposarcoma varies according to how far it has spread. A tumor discovered early may be removed using surgery. After further progression, removal is more difficult, and chemotherapy and radiotherapy may be used to treat the cancer instead. Although it is not known exactly how effective chemotherapy is for treating liposarcomas, it is thought that myxoid liposarcomas may be more responsive to chemotherapy than other types. With treatment, myxoid liposarcoma has a more positive prognosis than some other liposarcomas, with more than 80 percent of people expected to remain alive five years after being diagnosed.