What is liposarcoma?
Liposarcoma is soft tissue cancer that develops in fat cells. It can begin in any part of the body, but it usually forms in belly, legs or arms. Liposarcoma most often occurs in the fat layer just below the skin or in the soft tissues (muscles, fat, tendons and nerves).
Liposarcomas are also called lipomatous tumors. They usually grow slowly and do not cause pain. In some cases, they can grow very quickly and cause pressure on nearby tissue or organs.
Lipomatous tumors are similar to a common type of lump under the skin called lipomas. Lipomas are benign (not cancerous). Recognizing the difference between a lipoma and a liposarcoma (cancer) should be completed by an expert in sarcoma.
How common is liposarcoma?
Liposarcoma is not common. It makes up about 18 percent of soft tissue sarcomas. To put this in perspective, soft tissue sarcomas account for less than 1 percent of all cancers around the globe. Doctors diagnose liposarcoma in about 2,000 people in the U.S. every year.
Who is affected by liposarcoma?
Liposarcoma occurs more often in men than women. It is most common in men ages 50-65.
It rarely affects children, but when it does, doctors usually diagnose it during the teenage years. It does not affect any particular ethnic group more than others.
Symptoms and Causes
What causes liposarcoma?
Doctors are not sure what causes liposarcoma. Mutations (changes) in genes found in fat cells may cause cells to grow uncontrollably, causing a tumor. Doctors have also found links between liposarcoma and other factors. Prior exposure to radiation or certain chemicals such as vinyl chloride (a toxic chemical used in making plastic) may cause liposarcoma in some people. In other cases, liposarcoma occurs due to hereditary conditions that are passed down among family members.
What are the symptoms of liposarcoma?
Some people with liposarcoma have no symptoms other than being able to feel a painless lump. People often notice these lumps after an injury, but trauma is not known to be a direct causative effect.
You may notice symptoms as a lipomatous tumor grows and presses on surrounding nerves, muscles, or organs. Signs and symptoms of liposarcoma vary depending on the tumor’s location. They can include:
- Fatigue (extreme tiredness)
- Trouble breathing
- Unexplained swelling
Diagnosis and Tests
How is liposarcoma diagnosed?
Doctors use several tests to confirm a diagnosis of liposarcoma. These tests include:
- Biopsy: A doctor uses a needle to take a sample of tissue from the tumor. Reviewing the cell sample under a microscope can identify features of liposarcoma.
- Imaging tests: Tests such as CT scans and MRIs help doctors locate the tumor and determine if it is cancerous or benign.
- Physical exam: During a physical exam, a doctor looks at and feels the tumor.
Doctors classify liposarcoma into five types based on features of the cancer cells and how fast they grow. The kinds of liposarcoma are:
- Dedifferentiated: Usually begins with slow-growing cancer cells in the abdomen (belly), but can occur in the extremities or chest area, as well.
- Myxoid: Often develops in arms and legs, and has a tendency to spread to unusual locations, such as distant skin, muscle, or bones.
- Round cell: Often develops in the thigh and can involve changes in the chromosomes (proteins that carry genetic information) in cells
- Pleomorphic: The rarest type of liposarcoma and the most likely to return after treatment
- Well-differentiated: The most commonly diagnosed liposarcoma, with cells that grow slowly and closely resemble typical fat cells. This form is not known to metastasize (spread).
Some researchers use the category myxoid/round cell liposarcoma (MRCLS) to include both subtypes.
Management and Treatment
What are the treatments for liposarcoma?
Liposarcoma treatment depends on the type of cancer, whether it has spread, and if so, where. You may have a combination of more than one type of treatment for the disease.
The types and length of treatment vary depending on the type of cancer and whether it has spread. Your treatment options might include:
- Surgery: A doctor removes the tumor and some of the surrounding healthy tissue to make sure no cancer cells remain.
- Radiation therapy: Radiation oncologists (a type of cancer specialist) use high doses of X-rays to help decrease the risk of the tumor coming back when surgery is undergone. Oftentimes, people have radiation before surgery, so that the surgeon can remove less tissue.
- Chemotherapy: Anti-cancer drugs kill cancer cells throughout the body. Most chemotherapy is delivered with infusion (injected into a vein) or in pill form. In some cases, doctors use chemotherapy before surgery to make the tumor smaller. Doctors may recommend chemotherapy after surgery to kill any cancer cells left behind.
- Newer drugs for liposarcoma: Halaven® (eribulin) and Yondelis® (trabedectin) are approved for people who have not responded to earlier treatment, have widespread liposarcoma, or have cancers that cannot be removed via surgery.
What are the complications of liposarcoma?
In some cases, doctors must amputate (remove) an entire limb to treat liposarcoma. In these cases, people may use a prosthetic (artificial limb) after surgery.
The treatments for liposarcoma may cause complications on their own. Radiation and chemotherapy can cause some unpleasant side effects. These side effects often stop once treatment ends. They include:
- Hair loss
- Neuropathy (nerve damage)
How can you prevent liposarcoma?
You cannot prevent liposarcoma. You can reduce your risk of soft tissue cancers by avoiding long-term exposure to radiation and toxic chemicals such as vinyl chloride.
Who is at risk of developing liposarcoma?
Most liposarcomas occur in people without any known risk factors. But some people do have higher risk for liposarcoma. They include those who have:
- A family history of cancer
- Exposure to radiation for treatment for other cancers
- Long-term exposure to certain chemicals, such as vinyl chloride
Outlook / Prognosis
What is the prognosis (outlook) for people with liposarcoma?
Doctors can successfully treat many cases of liposarcoma. Sometimes people need more than one surgery to remove the cancer entirely and ensure it does not return. Each of the five subtypes carries a different prognosis, and should be discussed with your sarcoma physician.
In some cases, people with liposarcoma need to continue treatments, including chemotherapy or radiation, to keep the cancer from spreading to other parts of the body. These treatments may continue indefinitely to manage the disease.
After liposarcoma treatment, you should follow up with your doctor regularly, usually for at least 10 years. Your doctor can monitor you for signs of new tumor growth and treat you right away.
When should I see a healthcare provider about liposarcoma?
Contact your healthcare provider if you have a painless lump under the skin that’s larger than 5 centimeters (approximately the size of a golf ball) or if you experience other signs and symptoms of liposarcoma. If you have had liposarcoma, be sure to follow any schedule of testing or appointments that your healthcare provider suggests.
What questions should I ask my doctor about liposarcoma?
If you have liposarcoma, you may want to ask your doctor:
- What type of treatment is best for me?
- What is the likelihood of treatment curing the liposarcoma?
- What should I do to manage the side effects of treatment?
- How will treatment affect my work and daily life?
Are there organizations that can help people with liposarcoma?
You may find useful information from these organizations:
- American Cancer Society
Cancer helpline: 800.227.2345
- Rare Cancer Alliance
- Sarcoma Alliance
- Sarcoma Foundation of America
A list of support organizations can be found at http://sarcomahelp.org/resources.html.