Myxofibrosarcoma

Myxofibrosarcoma is a rare type of sarcoma that forms in the connective layers beneath the skin, often involving muscle, fat or fibrous tissue. It accounts for approximately 5 to 10% of all soft tissue sarcomas, with only a few hundred new cases diagnosed each year in the United States.

While myxofibrosarcoma primarily develops in the arms and legs of older adults, it can occur anywhere in the body and affect people of any age. Typically, the cancer grows slowly, but it can become aggressive if left untreated. It also tends to return if the tumor is not completely removed. With an early diagnosis and appropriate treatment, however, many patients can achieve an excellent long-term outcome and quality of life.

What are the causes and risk factors for myxofibrosarcoma?

The exact cause of myxofibrosarcoma is unknown. Scientists believe that, like most cancers, it likely results from abnormal cellular changes that cause the cells to grow uncontrollably and form tumors.

Risk factors for myxofibrosarcoma include:

• Prior radiation therapy for cancer treatment
• Certain inherited genetic conditions, such as Li-Fraumeni syndrome
• Long-term exposure to harmful industrial chemicals (rare)
• Advanced age, as the condition is most common in adults 50 and older

Is myxofibrosarcoma preventable?

Currently, there are no known ways to prevent myxofibrosarcoma. Because its cause is linked to spontaneous genetic mutations rather than lifestyle or environmental factors, prevention is difficult. However, the risk of developing the condition may be reduced by:

• Having regular health checkups and promptly discussing any unusual changes with a physician
• Avoiding unnecessary exposure to radiation therapy and toxic chemicals
• Seeking prompt treatment for any abnormal lumps or skin growths

What are the signs and symptoms of myxofibrosarcoma?

Myxofibrosarcoma often begins as a painless, slow-growing lump that can be seen or felt beneath the skin. Over time, the lump may increase in terms of size and firmness.

What are the early warning signs of myxofibrosarcoma?

In its early stages, myxofibrosarcoma may appear harmless and cause little to no discomfort. Early warning signs can include:

• A small, painless mass under the skin
• Swelling or fullness in an arm or leg
• A lump that gradually increases in size over several weeks or months

What are the most common symptoms of myxofibrosarcoma?

As the tumor grows, it may begin to affect the surrounding tissues and nerves. Common symptoms include:

• A firm, noticeable lump underneath the skin
• Mild pain or tenderness in the affected area
• Limited movement if the tumor presses on nearby muscles or joints

What are the symptoms of advanced myxofibrosarcoma?

As myxofibrosarcoma progresses, it may begin to cause more significant discomfort or changes in appearance. Symptoms of advanced myxofibrosarcoma may include:

• A large tumor that is visibly raised or irregular in shape
• Increased pain or sensitivity
• Skin changes, such as redness, thinning or ulceration over the tumor

What are some signs that myxofibrosarcoma has spread?

If myxofibrosarcoma spreads (metastasizes), it most often affects the lungs or other soft tissues. Signs that myxofibrosarcoma may have spread beyond its site of origin include:

• Shortness of breath or persistent cough
• Fatigue or unintentional weight loss
• New lumps in other parts of the body

How is myxofibrosarcoma diagnosed?

Diagnosing myxofibrosarcoma typically involves a physical examination, imaging studies and a biopsy to confirm the presence and type of cancer cells. An early diagnosis can expand the treatment options and significantly improve the outcome.

What laboratory tests are used to diagnose myxofibrosarcoma?

Lab testing can help the physician identify the specific cell types and genetic markers associated with myxofibrosarcoma. Common tests include:

• Biopsy with microscopic analysis to identify cancer cells
• Genetic or molecular testing to detect gene mutations that may guide treatment decisions

What imaging tests are used to diagnose myxofibrosarcoma?

Imaging plays an important role in helping the physician determine the size, location and spread of the tumor. Imaging tests that may be used to diagnose myxofibrosarcoma include:

• Magnetic resonance imaging (MRI) to show soft tissue details and tumor depth
• Computed tomography (CT) scans to evaluate the lungs or deeper tissues
• Positron emission tomography (PET) scans to detect distant cancer spread

What procedures are used to diagnose myxofibrosarcoma?

Certain diagnostic procedures can help the physician collect tissue samples or plan surgery for myxofibrosarcoma. Options may include:

• Core needle biopsy to remove a small tissue sample for testing
• Surgical biopsy or excision if the tumor is accessible and its full removal is necessary to confirm the diagnosis

How is myxofibrosarcoma treated?

The optimal treatment approach for myxofibrosarcoma can vary depending on the size, location and stage of the tumor. Most patients are treated with a combination of surgery, radiation therapy and, in some cases, chemotherapy or targeted therapy.

How is surgery used to treat myxofibrosarcoma?

Surgery is the primary treatment for most patients with myxofibrosarcoma. Common surgical techniques include:

• Wide local excision to remove the tumor along with some surrounding tissue to ensure clean margins
• Limb-sparing surgery to preserve function while removing all cancerous tissue
• Reconstructive surgery after tumor removal to restore mobility and appearance

How is radiation therapy used to treat myxofibrosarcoma?

Radiation therapy for myxofibrosarcoma may be administered:

• Before surgery to shrink the tumor for easier removal
• After surgery to help destroy any remaining cancer cells
• As an alternative to surgery to control the growth of an operable tumor

How is chemotherapy used to treat myxofibrosarcoma?

Chemotherapy is sometimes used for advanced or recurrent myxofibrosarcoma. Potential chemotherapy uses include:

• Treating cancer that has spread to other parts of the body
• Reducing the size of the tumor before surgery
• Managing cancer recurrence after previous treatment

How is targeted therapy used to treat myxofibrosarcoma?

Targeted therapy works by blocking specific molecules that help cancer cells grow. Research on targeted treatments for myxofibrosarcoma is ongoing.

Targeted therapy for myxofibrosarcoma may be considered if:

• The tumor has certain genetic mutations
• Standard treatments are not effective or tolerated

How is immunotherapy used to treat myxofibrosarcoma?

Immunotherapy can strengthen the body’s immune system, helping it to recognize and destroy cancer cells. While not a standard for myxofibrosarcoma, it is currently being studied in clinical trials.

Possible immunotherapy options include:

• Checkpoint inhibitors to help the immune system target cancer cells
• Clinical trial therapies that test new immune-based treatments for soft tissue sarcomas

Are there other treatment options for myxofibrosarcoma?

In addition to standard treatments for myxofibrosarcoma, some patients may benefit from clinical trials or supportive therapies. Options may include:

• Clinical trials offering early access to promising new treatments
• Repeat surgery if the tumor returns
• Supportive care to manage pain and maintain the quality of life for a patient with advanced cancer

My first experience it sounded like there was no hope. And when I came to Moffitt it was a totally different experience where there was hope, you know. There was going to be a silver lining at the end of all of this. And I was going to win.

Kevin

Sarcoma Survivor

What are some frequently asked questions (FAQs) about myxofibrosarcoma?

Due to the unique nature of myxofibrosarcoma, many people have questions about what it is, how it behaves and what treatment involves. Below are answers to some of the most commonly asked questions:

Is myxofibrosarcoma cancerous?

Yes. Myxofibrosarcoma is a type of soft tissue sarcoma, which means it is a form of cancer that develops in the connective tissues of the body.

Can myxofibrosarcoma come back after treatment?

Compared to other types of sarcoma, myxofibrosarcoma has a higher likelihood of recurrence, especially if the tumor was not completely removed. Regular follow-up visits and imaging scans are essential for long-term monitoring.

What is the prognosis for a patient with myxofibrosarcoma?

The outlook for a patient with myxofibrosarcoma will depend on several individual factors, including the size and location of the tumor and whether it can be completely removed. When the cancer is detected early and treated effectively, many patients have a good long-term prognosis.

Benefit from world-class care at Moffitt Cancer Center

If you have questions about myxofibrosarcoma, you can request an appointment with a specialist in the Sarcoma Program at Moffitt by calling 1-888-663-3488 or completing our new patient registration form online. We do not require referrals.