Soft Tissue Sarcoma Treatment: Understanding Your Options

Getting a soft tissue sarcoma diagnosis in undoubtedly frightening—but first off, know that you can fight it. “This is a curable cancer,” says Richard Bakst, MD, a radiation oncologist at Mount Sinai Hospital. That’s why it’s important for patients with soft tissue sarcoma, a type of cancer that forms from soft tissues which connect and support other tissues in the body (like the muscles, tendons, nerves, and blood vessels), to know their treatment options so they can work with their doctor to find the best treatment path for their disease.

Testing for Soft Tissue Sarcoma

After diagnosing soft tissue sarcoma, the next step is to [take images] of both the tumor’s site and of the rest of the body to understand where there is or isn’t disease, says Dr. Bakst. Typically patients may get magnetic resonance imaging (MRI) at the site of the sarcoma, followed by a positron emission tomography (PET) scan, which is where radioactive tracers look for other cancer cells that may be lingering in the body. Additionally, patients may also get a computed tomography (CT) scan to make sure that there’s no cancer in the lungs. When it metastasizes, soft tissue sarcoma has a tendency to spread to the lungs.

Soft Tissue Sarcoma Treatment Options

Soft tissue sarcoma can be treated with standard treatments (treatment options that are currently used and recommended), as well as treatments being tested in clinical trials (research studies meant to help improve current treatments or obtain information on new treatments for patients with cancer).

Surgery: Surgery is the most common soft tissue sarcoma treatment. “Surgery is meant to remove the mass that the surgeon can see, both with their eyes, and on imaging,” says Bakst. The goal of surgery is to remove the entire tumor along with at least 1 to 2 cm (less than an inch) of the normal tissue surrounding the tumor. This is to make sure that no cancer cells are left behind. In some cases, surgery may be the only treatment for soft tissue sarcoma needed.

Radiation therapy: Radiation therapy uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. “Radiation is intended to eradicate microscopic disease that may be left behind, that the surgeon can’t see with his or her eye or that can’t be picked up on the scan,” says Dr. Bakst. “Sometimes proceeding surgery, radiation is administered, or following surgery, radiation can also be administered as well.”

Chemotherapy: Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. “In general, patients don’t receive chemotherapy as part of their upfront care in soft tissue sarcoma, however, each patient is evaluated individually, and the risks and benefits of treatment of chemotherapy are usually weighed,” says Dr.  Bakst.

Immunotherapy: Immunotherapy is a treatment that harnesses the power of the immune system to fight cancer. “There’s a great deal of interest in looking at the role the immune system plays [in] allowing sarcomas to develop, or using it to attack the sarcoma cells,” says Bakst.

For soft tissue sarcoma, the main immunotherapy approaches involve medications called checkpoint inhibitors and adoptive T cell therapy. Checkpoint inhibitors are drugs that block specific proteins on the surface of immune system T cells. This releases a natural brake on the immune system, allowing it to attack the cancer. Adoptive T cell therapy involves removing T cells from patients and modifying them in a way that enables them to recognize and attack specific molecules on the surface of cancer cells.

Targeted therapy: Targeted therapy is a newer type of cancer treatment that uses drugs to attack cancer cells while doing little harm to normal cells. Each type of targeted therapy works differently, but all alter the way a cancer cell grows, divides, repairs itself, or interacts with other cells. Some of these drugs are:

• Olaratumab (Lartruvo), which is a monoclonal antibody that prevents a protein called platelet-derived growth factor (PDGF) receptor-alpha from binding with cancer cells. By disrupting this binding process, the drug may help block growth-promoting signals in cancer cells.
• Pazopanib (Votrient), which blocks several cellular enzymes called tyrosine kinases that are important for cell growth and survival. Alongside chemo, pazopanib stopped the cancers from growing for an average of about three months longer than the patients given a sugar pill.
• Imatinib (Gleevec), which is a tyrosine kinase inhibitor drug that may be helpful in treating desmoid tumors (tumors that grow from connective tissues) that can’t be removed with surgery.

“I would ask your doctor, ‘what subclass of soft tissue sarcoma do I have?’ Because in the future we may have targeted therapies for certain types of sarcoma, and they also may be monitored and treated slightly differently,” says Dr. Bakst.

Current clinical trials: Clinical trials are currently studying the ways to improve the effect chemotherapy has on tumor cells, like: 

• Regional hyperthermia therapy. A treatment in which tissue around the tumor is exposed to high temperatures to damage and kill cancer cells or to make cancer cells more sensitive to chemotherapy.
• Isolated limb perfusion. A procedure that sends chemotherapy directly to an arm or leg in which the cancer has formed. The flow of blood to and from the limb is temporarily stopped with a tourniquet, and anticancer drugs are put directly into the blood of the limb. This sends a high dose of drugs to the tumor.

“When I’m treating patients for soft tissue sarcoma I tell them to focus on the task at hand. So if it’s to get through surgery and recover, focus on that, if it’s to get through radiation, focus on that. Don’t think too far ahead, and after the treatment is done, we’ll get you back to a normal life,” says Dr. Bakst.