Dedifferentiated Liposarcoma

Dedifferentiated liposarcoma (DDLS) is a high-grade sarcoma that develops from a preexisting well-differentiated liposarcoma (WDLS). This subtype is more aggressive than WDLS but less aggressive than other high-grade sarcomas, where tumor cells grow and spread at a rapid pace.

DDLS typically affects middle-aged and older adults, with a slight predominance in men. Compared to other liposarcoma subtypes, DDLS has a higher likelihood of local recurrence and metastasis, posing a more significant challenge for treatment.

At Sarcoma Oncology Center, we offer cutting-edge treatment options for dedifferentiated liposarcoma, grounded in the latest research, clinical trials, and innovative therapies. Our approach ensures that every treatment plan is carefully tailored to meet the unique needs of each patient.

Understanding Dedifferentiated Liposarcoma

Dedifferentiated liposarcoma refers to the transition from well-differentiated liposarcoma to non-lipogenic sarcoma, which arises mainly in the retroperitoneum (the back of the abdominal cavity) and deep soft tissue of the upper arms and legs.

Dedifferentiation usually happens over time, and in about 90% of cases, dedifferentiated liposarcoma develops on its own. In the other 10% of cases, it occurs when a previously treated well-differentiated liposarcoma returns in a more aggressive form.

Unlike WDLS, DDL is a high-grade and aggressive tumor, with a 41% to 52% chance of coming back in the same area, a 15% chance of spreading to other parts of the body, and a 30% chance of disease-related mortality rate.

The tumor’s location plays a big role in the outcome. Studies suggest that DDL cases that occur in the arms or legs tend to have better outcomes than those that develop in the retroperitoneum.

Symptoms of Dedifferentiated Liposarcoma

Dedifferentiated liposarcoma typically appears as a large, painless lump that may have grown slowly over several years. When located in the abdominal cavity, it is often discovered incidentally during imaging tests for other reasons.

Symptoms generally depend on the tumor’s location and size. Common signs include:

New and large lump under the skin, often found on the arm, leg, or torso
Painful swelling or numbness near the lump
Digestive issues such as constipation
Abdominal pain, cramping, or swelling
Blood in the stool or vomit
Difficulty breathing or persistent cough

Causes of Dedifferentiated Liposarcoma

Dedifferentiated liposarcoma often shares the same genetic abnormalities as well-differentiated liposarcoma. It includes amplification of the chromosomal region 12q13-15, where the number of copies of genes like MDM2 and CDK4 increases. These genes help in tumor growth by disrupting normal cell processes.

Researchers have recently found specific gene fusions (when two or more genes join together to form a new gene) in some DDL cases. However, it’s still unclear exactly how WDL progresses to DDL.

Diagnosis of Dedifferentiated Liposarcoma

Dedifferentiated liposarcoma is composed of two types of tissue: one resembling a well-differentiated liposarcoma and the other a non-fatty sarcoma. Diagnosing DDL involves a thorough evaluation using multiple diagnostic methods to understand the tumor’s nature and location.

Physical Examination: Your doctor checks for noticeable lumps or masses by examining and feeling the affected area.
Imaging: Imaging tests such as CT scans or MRIs help assess the tumor’s size, location, and extent. These scans also determine if the tumor has spread to nearby tissues or other parts of the body.
Biopsy: A biopsy involves taking a tissue sample, often using an image-guided needle biopsy, and analyzing it under a microscope to identify the tumor’s characteristics.
Molecular and Genetic Testing: Specialized tests analyze the genetic and molecular features of the tumor, providing insights into its behavior. PET scans are often used to study the tumor’s metabolism.

Most DDL cases show high levels of the protein MDM2, which serves as a critical marker for this type of sarcoma. Testing for MDM2 is highly recommended for an accurate and early diagnosis of dedifferentiated liposarcoma.

Treatment of Dedifferentiated Liposarcoma

Treatment for dedifferentiated liposarcoma may involve a multimodal approach coupled with considerations for the uniqueness of each case.

Surgery is the standard treatment for localized DDL, with or without radiation. For more advanced cases, chemotherapy is usually the first option, but it may not always lead to the best outcomes.

At Sarcoma Oncology Center, when deciding on surgery, our experienced oncology team chooses the most appropriate approach based on the tumor's size, location, and how it’s connected to nearby structures like blood vessels, nerves, or bones.

Ongoing clinical trials are exploring innovative therapies to target the MDM2 protein, which interferes with your body’s tumor-suppressing abilities. This treatment is still being researched and shows promise in fighting DDL. Immunotherapy, which boosts the body’s immune system to fight cancer, is another potential treatment option for dedifferentiated liposarcoma.

Dedifferentiated Liposarcoma Treatment at Sarcoma Oncology Center

A collaborative, multidisciplinary approach is critically important to treat dedifferentiated liposarcoma. Our team of specialists design personalized treatment plans based on the latest research and advanced therapies to offer you the best possible medical care.

At our office in Santa Monica, we design personalized and innovative plans for treating dedifferentiated liposarcoma.

To schedule a consultation, please call us at 424-699-3862 or request an appointment online.