A group of rare cancers that begin to develop in fat cells in the legs or arms is called liposarcoma. While most of them are removed surgically, some of them may recur. That’s why doctors may prescribe additional treatment and long-term follow-up. It also helps detect new tumors in the early stages before they spread.
Generally, this type of cancer occurs rarely, and it affects about 4 in 100,000 people in the United States each year.
How Does a Liposarcoma Affect My Body?
The effects of this type of cancer usually depend on the type of liposarcoma you develop. For instance, a tumor in the arms or legs (particularly in the thighs or back of the knees) usually does not cause symptoms in the early stages and grows slowly. Sometimes, you may notice a lump on the arm or leg that does not go away or gets larger. Most of the time, the tumor causes pain when it puts pressure on a nearby nerve or organ. For example, if the tumor develops in the lungs, you may have breathing problems.
Types of Liposarcoma
Healthcare professionals have divided this type of cancer into several types. These include:
- Well-differentiated liposarcoma (WDLS) – This is one of the most common forms of liposarcoma, and it accounts for about 40% to 50% of all diagnosed cases. While the tumor mostly appears in the arms or legs, some people may develop it in the trunk. Sometimes, it is called atypical lipomatous tumors.
- Myxoid and round cell liposarcomas – These forms of liposarcoma are the second most common types, and they account for about 30% of all cases. In most cases, the tumor develops in the legs and may easily spread to nearby soft tissues (including the muscles and skin). In more advanced stages, these types of liposarcoma may spread to the pelvic bones, spine, or organs (such as the heart, lungs, or esophagus).
- Dedifferentiated liposarcoma (DDLS) – Sometimes, people with WDLS also develop DDLS. Unfortunately, DDLS is an aggressive form of liposarcoma that often appears in the back of the abdomen (belly). Sometimes, it may also appear in the arms or legs. Moreover, DDLS may return even after a successful surgery. Approximately 45% of people with DDLS live 5 years after diagnosis.
- Pleomorphic liposarcoma – This is a rare form of liposarcoma, which accounts for about 5% to 10% of all liposarcomas, but has the worst survival rate. While most tumors develop in the arms and legs, some people may develop them in the back of the abdomen or chest wall. The tumor often grows quickly and may easily spread to the lungs.
Is Liposarcoma An Aggressive Cancer?
Not all types of liposarcoma are aggressive. For instance, WDLS and DDLS are slow-growing tumors that often appear in the arms or legs and are not life-threatening. However, if you develop a myxoid or dedifferentiated liposarcoma, it can spread to other parts of the body and recur after treatment. Furthermore, a pleomorphic liposarcoma is a very aggressive form of cancer that frequently spreads to the lungs.
What Are The Symptoms of Liposarcoma?
Typically, people with liposarcoma experience different symptoms because they depend on the size and location of the tumor. Some people may notice a lump or bump under the skin. Check some general symptoms of liposarcoma below:
- Swelling or pain (particularly a swollen abdomen)
- Weakness in the arm or leg where the tumor grows
- Appetite changes
- Constipation
- Bloody and black or tarry stools
- Breathing problems
- Cramps
- Bloody vomit
- Feeling full soon after beginning to eat
- A lump under the skin (especially around or behind the knees or on the thighs)
If any of the previous symptoms occur, immediately contact your healthcare professional for a diagnosis. Otherwise, it may lead to serious outcomes.
Causes
This type of cancer occurs like many others due to certain genetic changes. In this case, genes that are responsible for fat cell growth are affected. When they are affected, these cells begin to grow and multiply abnormally. Nowadays, there are more than 20 different genetic changes (mutations) that cause liposarcoma. Experts do not understand what exactly causes these genetic changes. However, they have identified some factors that may contribute to liposarcoma. These include:
- Radiation therapy
- Long-term exposure to workplace chemicals (such as vinyl chloride)
- Certain inherited disorders (such as Li-Fraumeni syndrome or hereditary retinoblastoma)
- Age – Most of the time, liposarcoma affects people between the ages of 50 and 65.
What Happens if Liposarcoma is Left Untreated?
People who ignore the symptoms and leave this type of cancer untreated may also experience some complications. Check some examples below:
- Limited range of motion and mobility
- Shortness of breath (dyspnea)
- Chronic (long-term) cough
- Urinary tract obstruction
- Gastrointestinal bleeding
- Severe constipation
- Dysphagia (swallowing problems)
- Metastasis – this complication occurs when the tumor grows large enough and breaks. As a result, cancerous cells spread to other parts of the body, including the lungs, liver, and other soft tissues.
- Treatment complications – These include blood loss, surgical wounds that do not heal, infections, damage to other organs, pain that does not disappear with pain relievers, extreme fatigue, lymphedema, and others.
This document does not contain a full list of liposarcoma complications. In any case, doctors may recommend some ways to reduce the risk or even prevent them. Unfortunately, there is no way to prevent liposarcoma because doctors do not fully understand what exactly causes it.
Diagnosis
First, doctors will perform a physical examination to check for abnormalities linked to the disease (such as a lump or bump), and may ask some questions about your symptoms and medical history to get more information. However, to confirm or rule out liposarcoma, doctors usually perform the following tests and procedures. Examples include:
- CT (computed tomography) scan – This imaging test is used to determine the exact location of the tumor.
- MRI (magnetic resonance imaging) scan – This is another imaging test used to get detailed images of nearby nerves, blood vessels, and muscles.
- Biopsy – During this procedure, doctors will take a small sample of the tumor for testing.
- Molecular and genetic tests – These tests are used to check for abnormal genes often present in people with liposarcoma and the type of cancer you have developed.
Treatment
While the primary treatment for liposarcoma is surgery to remove the tumor, doctors may recommend additional treatments if the tumor spreads to other parts of the body or the cancer recurs after successful treatment. Check some examples below:
- Chemotherapy – This cancer treatment involves strong medicines that destroy cancerous cells throughout the body. It can be prescribed by doctors before surgery to shrink a large tumor or after surgery to destroy the remaining cancer cells. When surgery is not an option, doctors may recommend radiation therapy to improve the effectiveness of the treatment.
- Radiation therapy – This is another cancer treatment that uses powerful energy beams to destroy cancerous cells. While most of the time, this energy comes from protons and X-rays, it may also come from other sources.
Frequently Asked Questions
Is liposarcoma the same as a lipoma?
No. A lipoma is a common, noncancerous (benign) tumor made of fat cells, while liposarcoma is a rare cancer that develops in fatty tissue. Although both can appear as lumps under the skin, liposarcoma may continue to grow, invade nearby tissues, or spread to other parts of the body. A healthcare professional should evaluate any lump that is enlarging or causing symptoms.
Where does liposarcoma usually develop?
Liposarcoma most commonly develops in the deep soft tissues of the thighs or behind the knees. However, it can also occur in the arms, buttocks, shoulders, chest wall, or the retroperitoneum (the area behind the abdominal organs). The location often influences the symptoms and treatment options.
Can liposarcoma spread to other parts of the body?
Yes. Some types of liposarcoma, especially pleomorphic, dedifferentiated, and high-grade myxoid liposarcomas, can spread (metastasize). The lungs are the most common site of metastasis, but the cancer may also spread to bones, the liver, or other soft tissues.
How is liposarcoma different from other soft tissue sarcomas?
Liposarcoma is one of more than 50 types of soft tissue sarcomas. It specifically begins in fat cells or fatty tissue, whereas other soft tissue sarcomas arise from muscles, blood vessels, nerves, fibrous tissue, or connective tissue. The exact treatment and prognosis depend on the specific sarcoma subtype.
Can liposarcoma come back after treatment?
Yes. Liposarcoma may recur even after the tumor has been completely removed with surgery. The risk of recurrence depends on factors such as the tumor type, grade, size, location, and whether all cancerous tissue was removed. Regular follow-up appointments and imaging tests help detect recurrence as early as possible.
What is the survival rate for liposarcoma?
Survival rates vary significantly depending on the subtype, tumor size, stage, location, and whether the cancer has spread. Well-differentiated liposarcomas generally have an excellent prognosis, while pleomorphic and dedifferentiated liposarcomas tend to have lower survival rates because they are more aggressive. Your healthcare provider can give a more accurate prognosis based on your individual case.
Who is at higher risk of developing liposarcoma?
Although anyone can develop liposarcoma, it is most commonly diagnosed in adults between 50 and 65 years of age. Previous radiation therapy, certain inherited genetic conditions (such as Li-Fraumeni syndrome or hereditary retinoblastoma), and long-term exposure to specific industrial chemicals may increase the risk.
How often should someone be monitored after liposarcoma treatment?
Follow-up schedules vary depending on the tumor type and stage. Many people need regular physical examinations and imaging tests, such as CT or MRI scans, every few months during the first few years after treatment. Over time, follow-up visits may become less frequent if there are no signs of recurrence.
Does every lump under the skin mean liposarcoma?
No. Most lumps under the skin are benign conditions, such as lipomas or cysts. However, any lump that is larger than 5 centimeters (about 2 inches), grows rapidly, is painful, or is located deep beneath the skin should be evaluated by a healthcare professional to rule out liposarcoma or another serious condition.
Can liposarcoma be cured?
Yes, some cases of liposarcoma can be cured, particularly when the cancer is diagnosed early and completely removed with surgery before it spreads. However, because certain types have a higher risk of recurrence or metastasis, long-term follow-up is essential even after successful treatment. Ask your healthcare professional if you have any other questions.
