Clear Cell Sarcoma

What is clear cell sarcoma?

Clear cell sarcoma is a very rare form of soft tissue sarcoma. Clear cell sarcoma causes tumors that typically start in the soft tissues that surround and support the tendons and muscles in your lower legs or feet. Like many kinds of cancer, clear cell sarcoma is easier to treat before it spreads. Healthcare providers treat this condition with surgery, chemotherapy and radiation therapy, but it often comes back (recurs) after treatment. Medical researchers are investigating new ways to treat tumors caused by clear cell sarcoma.

How does clear cell sarcoma affect my body?

Clear cell sarcoma typically starts in the deep soft tissues surrounding your tendons and muscles or in your fascia. (That’s the band of stringy tissue wrapped around every structure in your body.)

You might not notice any change until the cancer has grown large enough to make a lump under the skin on your foot or leg. The lump looks like the kind of lump you’d get if you took a hard hit on your leg or foot. The difference is that this lump doesn’t go away. Clear cell sarcoma grows very slowly. But at the same time that it moves from your deep soft tissues to just under your skin, it may spread to other areas of your body.

Where does clear cell sarcoma spread?

Clear cell sarcoma may spread to your gastrointestinal tract, your lungs or your lymphatic system.

Is clear cell sarcoma a common condition?

No, it’s an example of a very rare subtype of a rare condition. Each year, about 1,600 people in the U.S. are diagnosed with a sarcoma. Sarcomas make up only 1% of all adult cancer diagnoses in the U.S. Clear cell sarcomas represent 1% of all sarcomas in the U.S.

Who’s affected by clear cell sarcoma?

People may develop clear cell sarcoma at any age, but it typically affects teenagers and young adults in their 20s and 30s. People who are white are more likely to develop clear cell sarcoma than people who are Black or Asian American.

What are clear cell sarcoma symptoms?

The most common symptom is a lump under your skin on your leg or foot. The lump may not hurt, but it doesn’t go away. You may notice the lump seems to get larger. Later, you may notice the following symptoms:

• Fatigue.
• Unexplained weight loss.
• Night sweats.

What causes clear cell sarcoma?

Clear cell sarcoma happens when two genes from different chromosomes swap places, creating what medical researchers call a fused or fusion gene.

This process starts when two chromosomes break apart. The broken sections from each chromosome carry the genes EWSR1 and ATF1. The EWSR1 gene is a protein that appears to play a role in how cells function. The ATF1 gene helps manage cell growth. The chromosomes come back together, but they now contain genes that don’t belong there. Medical researchers call this reciprocal translocation. Researchers don’t know what triggers reciprocal translocation.

Once they’re in their new chromosomal home, the relocated genes combine with other genes to make the fused gene EWSR1/ATF1. Researchers believe the fused gene causes clear cell sarcoma.

How do healthcare providers diagnose clear cell sarcoma?

Healthcare providers may do a physical exam to determine the tumor location and approximate size. They may also do magnetic resonance imaging (MRI) scans. But healthcare providers typically diagnose clear cell sarcoma based on tissue samples taken during biopsies. Medical pathologists examine these samples under microscope, looking for the fusion gene EWRS1/AFT1.

How do healthcare providers treat clear cell sarcoma?

Healthcare providers typically focus treatment on keeping clear cell sarcoma from spreading. Most of the time, they do surgery to remove the tumor and any lymph nodes where the tumor has spread. Next comes adjuvant therapy — usually radiation therapy to kill any remaining cancer cells.

Medical researchers are evaluating other treatments, including immunotherapy, which may do more to control clear cell sarcoma. They’re also testing drugs now used to treat other cancers to see if those drugs may stop clear cell sarcoma from spreading.

Clear cell sarcoma often comes back, requiring more surgery and additional radiation therapy. The condition also spreads very quickly, which means healthcare providers need to monitor for symptoms of new tumors.

Can I reduce my risk of developing clear cell sarcoma?

Unfortunately, you can’t do anything to reduce your risk of developing this condition. Medical researchers haven’t identified specific risk factors for clear cell sarcoma. A risk factor is an activity or condition that makes it more likely some will develop a specific illness.

Can clear cell sarcoma be cured?

Healthcare providers can treat clear cell sarcoma, but they can’t cure it. Many times, clear cell sarcoma isn’t diagnosed until after it’s spread to other areas of your body, making it more difficult to treat. Clear cell sarcoma often comes back after treatment.

What’s the life expectancy for clear cell sarcoma?

Life expectancy is an estimate of how long you’ll live, given your overall health and personal circumstances. A 2018 review of the U.S. National Cancer Database showed 50% of people with clear cell sarcoma were alive five years after diagnosis. The review showed 38% of people were alive 10 years after diagnosis.

Whether we’re talking about life expectancy or survival rates, it’s important to remember these are estimates and not predictions. Life expectancy is an estimate based on the population as a whole. Cancer survival rates are estimates based on outcomes — how long people lived after treatment for specific types of cancer. Many things affect life expectancy or surviving cancer. If you have clear cell sarcoma, your healthcare provider is your best resource for information about what you can expect.

Is clear cell sarcoma a fatal illness?

It can be. In general, people with clear cell sarcoma that’s spread to other parts of their body die sooner than people whose cancer was treated before tumors spread.

When should I see my healthcare provider?

Clear cell sarcoma often comes back (recurs) after treatment. Depending on your situation, your healthcare provider may want to see you every three months for the first two years after you complete treatment.

What questions should I ask my healthcare provider?

Clear cell sarcoma is a very rare disease. It can be a life-threatening disease. If you’ve been diagnosed with this condition, here are some questions you may want to ask your healthcare provider:

• Where’s the tumor?
• How big is it?
• Has the tumor spread anywhere else in my body?
• What treatments do you recommend?
• What are treatment side effects?
• If I have surgery, what are the chances the tumors will come back?
• Are there clinical trials I should consider?

A note from Cleveland Clinic

Clear cell sarcoma is a challenging disease. It’s very rare. Each year, only a handful of people in the U.S. are diagnosed with clear cell sarcoma. It grows very slowly. Most people don’t notice changes in their bodies until the sarcoma has spread. Healthcare providers can treat clear cell sarcoma with surgery to remove tumors and follow-up treatment to kill any cancer cells that remain. Unfortunately, clear cell sarcoma often comes back. Medical researchers are evaluating new ways to treat clear cell sarcoma. If you have clear cell sarcoma and are interested in learning about clinical trials, ask your healthcare provider for help.