Liposarcoma

Liposarcoma is a group of very rare cancers that begin in your fat cells. You can develop a liposarcoma in any part of your body, but these tumors typically begin in your belly, arms and legs. Healthcare providers treat liposarcoma with surgery to remove tumors. Some types of liposarcoma may come back, requiring additional treatment and long-term follow up to catch new liposarcomas before they can spread.

How does a liposarcoma affect my body?

That depends on what kind of liposarcoma you have. In general, liposarcomas develop in your arms or legs, particularly in your thighs or the back of your knees, but you can also develop liposarcoma in the back of your belly.

Most liposarcomas grow very slowly and rarely cause pain. You may not notice any changes in your body unless you notice a large bump on your arm or leg that doesn’t go away or gets larger. A liposarcoma may cause pain if it presses on a nerve. Likewise, a liposarcoma may affect some of your organs. For example, a liposarcoma in your lungs may make it hard for you to breathe.

How common is this condition?

Liposarcoma isn’t common. It’s a rare form of soft tissue sarcoma, which affects approximately 4 in 100,000 people in the U.S. each year. Liposarcoma affects 1 in 100,000 people in the U.S. each year.

Who does this condition affect?

Liposarcoma typically affects more men and people assigned male at birth (AMAB) than women and people assigned female at birth (AFAB). It’s often found in men and people AMAB between ages 50 and 65, but one type of liposarcoma affects people ages 35 to 55.

Is liposarcoma an aggressive cancer?

There’s a wide range of liposarcomas. Some, such as well-differentiated liposarcoma or atypical lipoma of the extremities (arms and legs), grow slowly and aren’t life-threatening. Other types, such as myxoid liposarcoma or dedifferentiated liposarcoma, are likely to spread or come back after treatment. A pleomorphic liposarcoma can be very aggressive, growing very fast and quickly spreading from where it started to other areas of your body.

What are the types of liposarcoma?

There are several liposarcoma types. The types have similar symptoms but can require different treatments and have different prognoses or expected outcomes.

Well-differentiated liposarcoma (WDLS)

This is the most common type, accounting for 30% to 50% of all liposarcomas. These are slow-growing painless tumors. They may appear in your arms and legs or your trunk. Providers may call them atypical lipomatous tumors. When you have a liposarcoma in the back of your abdomen/belly (retroperitoneum), it’s called a well-differentiated liposarcoma.

Myxoid liposarcoma/round cell liposarcoma

These are the second most common types of liposarcoma, accounting for about 30% of all liposarcomas. Unlike other types, myxoid liposarcoma may affect people age 35 to 55. Tumors in this type of liposarcoma usually develop in people’s legs. It can spread to nearby soft tissue, including muscle and skin. You can also have this liposarcoma type in your bones, such as your pelvic bones or your spine, or organs such as your heart, lungs or your esophagus.

The term “round cell” refers to how tumor cells appear when viewed under a microscope. Round cell liposarcomas account for more than 5% of liposarcomas and are an aggressive form of liposarcoma.

Dedifferentiated liposarcoma (DDLS)

Some people with WDLS develop dedifferentiated liposarcoma. Unlike WDLS, this is usually a fast-growing tumor. DDLS typically appears in the back of people’s bellies, but may also affect their arms and legs. Like WDLS, providers treat DDLS with surgery. DDLS often come back after surgery. Overall, 44% of people with this condition were alive five years after diagnosis.

Pleomorphic liposarcoma

Pleomorphic liposarcoma is the least common form, accounting for 5% to 10% of all liposarcomas. It usually appears in people’s arms and legs, but can start in the back of their bellies or chest wall. Pleomorphic liposarcoma grows very fast, often spreading to people’s lungs. This type of liposarcoma has the worst survival rate.