This rare type of cancer can begin in the muscles, fat, blood vessels, nerves, tendons and the lining of joints. Treatment usually includes surgery.
Soft tissue sarcoma is a rare type of cancer that starts as a growth of cells in the body's soft tissues. The soft tissues connect, support and surround other body structures. Soft tissues include muscle, fat, blood vessels, nerves, tendons and linings of the joints.
Soft tissue sarcoma can happen anywhere in the body. It happens most often in the arms, legs and belly.
More than 50 types of soft tissue sarcoma exist. Some types are more likely to affect children. Others affect mostly adults. These cancers can be hard to diagnose because they may be mistaken for many other types of growths.
Soft tissue sarcoma treatment usually involves surgery. Other treatments might include radiation therapy and chemotherapy. Treatment depends on the size, type and location of the cancer and how quickly it grows.
Soft tissue sarcomas are cancers that start in the soft tissues of the body. This illustration shows a soft tissue sarcoma of the thigh muscle just above the knee.
A soft tissue sarcoma may not cause any symptoms at first. As the cancer grows, it may cause:
Make an appointment with your health care team if you have any symptoms that worry you.
It's not clear what causes most soft tissue sarcomas.
Soft tissue sarcoma starts when a connective tissue cell gets changes in its DNA. A cell's DNA holds the instructions that tell a cell what to do. The changes turn the connective tissue cells into cancer cells. The changes tell the cancer cells to grow and make more cells. Healthy cells die as part of their natural cycle, but cancer cells keep growing because they do not have instructions to stop.
The cancer cells form a growth, called a tumor. In some types of soft tissue sarcoma, the cancer cells stay in one location. They continue making more cells and cause the tumor to get bigger. In other types of soft tissue sarcoma, the cancer cells might break away and spread to other parts of the body.
The type of cell with DNA changes is what determines the type of soft tissue sarcoma. For example, angiosarcoma begins in cells in the lining of blood vessels, while liposarcoma starts in fat cells.
Some types of soft tissue sarcoma include:
Factors that may raise the risk of sarcoma include:
Tests and procedures used to diagnose soft tissue sarcoma include imaging tests and procedures to remove a sample of cells for testing.
Imaging tests create pictures of the inside of the body. They might help show the size and location of the soft tissue sarcoma. Examples include:
A procedure to remove some cells for testing is called a biopsy. A biopsy for soft tissue sarcoma needs to be done in a way that won't cause problems with future surgery. For this reason, it's a good idea to seek care at a medical center that sees many people with this type of cancer. Experienced health care teams will select the best type of biopsy.
Types of biopsy procedures for soft tissue sarcoma include:
The biopsy sample goes to a lab for testing. Doctors who specialize in analyzing blood and body tissue, called pathologists, will test the cells to see if they're cancerous. Other tests in the lab show more details about the cancer cells, such as what type of cells they are.
Treatment options for soft tissue sarcoma will depend on the size, type and location of the cancer.
Surgery is a common treatment for soft tissue sarcoma. During surgery, the surgeon usually removes the cancer and some healthy tissue around it.
Soft tissue sarcoma often affects the arms and legs. In the past, surgery to remove an arm or leg was common. Today, other approaches are used, when possible. For example, radiation and chemotherapy might be used to shrink the cancer. That way the cancer can be removed without needing to remove the entire limb.
Radiation therapy uses powerful energy beams to kill cancer cells. The energy can come from X-rays, protons and other sources. During radiation therapy, you lie on a table while a machine moves around you. The machine directs radiation to specific points on your body.
Radiation therapy might be used:
Chemotherapy uses strong medicines to kill cancer cells. The medicines are often given through a vein, though some are available in pill form. Some types of soft tissue sarcoma respond better to chemotherapy than do others. For instance, chemotherapy is often used to treat rhabdomyosarcoma.
Targeted therapy uses medicines that attack specific chemicals in the cancer cells. By blocking these chemicals, targeted treatments can cause cancer cells to die. Your cancer cells might be tested to see if targeted therapy might be helpful for you. This treatment works well for some types of soft tissue sarcoma, such as gastrointestinal stromal tumors, also called GISTs.
During intraoperative radiation therapy (IORT), radiation is directed to where it's needed. The dose of IORT can be much higher than is possible with standard radiation therapy.
A diagnosis of cancer can feel overwhelming. With time you'll find ways to cope with the distress and uncertainty of cancer. Until then, you may find it helps to:
Make an appointment with your usual doctor or other health care professional if you have any symptoms that worry you. If your doctor thinks you might have soft tissue sarcoma, you'll likely be referred to a cancer doctor, called an oncologist. Soft tissue sarcoma is rare and is best treated by someone who has experience with it. Doctors with this kind of experience are often found within an academic or specialized cancer center.
Preparing a list of questions can help you make the most of your appointment time. List your questions from most important to least important in case time runs out. For soft tissue sarcoma, some basic questions to ask include:
Be prepared to answer some basic questions about your symptoms and your health. Questions might include: