Types of Soft Tissue Sarcoma

Soft tissue sarcoma is a type of cancer that develops from the soft tissues of the body, including the muscles, tendons, connective tissues, fat, blood vessels, nerves, or joint tissues. Understanding what type of sarcoma is present helps our doctors develop an effective treatment plan.

NYU Langone doctors are experts in diagnosing the more than 50 subtypes of soft tissue sarcoma, no matter how rare. The following are some of the more common subtypes.

Undifferentiated Pleomorphic Sarcoma

Undifferentiated pleomorphic sarcomas are rapidly growing cancers that can occur in the arms, legs, or deep within the abdomen. This classification of tumor now includes what were once called fibrosarcoma, malignant fibrous histiocytoma, myofibroblastic sarcoma, and malignant spindle cell sarcoma. Under a microscope, their cells appear to be spindle-like, or long and tapered on the end.

These are all cancerous soft tissue sarcomas that behave in the same way. They arise from mensenchymal tissue, which forms connective tissue. This cancer can appear as a painless lump under the skin

Treatment may include a combination of surgery, radiation therapy, which is the use of high levels of energy to kill cancer cells, and chemotherapy, which is a group of drugs that help to destroy cancer cells throughout the body.

Liposarcoma

Liposarcomas, one of the more common types of soft tissue sarcoma, are cancerous tumors that develop from fat tissue, most often in the thighs or deep within the abdomen. Symptoms include a painless lump under the skin.

Some liposarcomas are very slow growing and respond well to treatment with surgery. Others grow rapidly and require an aggressive treatment plan that includes surgery, radiation therapy, or possibly chemotherapy. Our doctors use genetic and molecular testing of the tumor to determine what type of liposarcoma is present and how best to treat it.

Angiosarcoma

Most angiosarcomas are cancerous tumors arising from the inner lining of the blood vessels. They can occur in the skin, the spleen, the liver, or breast tissue. When they develop on the skin, they sometimes look like a bruise or an infection, or they may appear as a soft, small red spot.

They may occur on the skin after radiation therapy, often in women who are in remission from breast cancer. They can also develop on the head and face, usually in men older than age 60, or in the soft tissue of younger adults. The location of the tumor often guides individualized treatment plans, which may include surgery, chemotherapy, and radiation therapy.

Solitary Fibrous Tumor

Although this growth was once described as slow growing and not likely to spread, many solitary fibrous tumors, also known as SFTs, can spread to other parts of the body after treatment. Many are found on the lining of the lungs, but they can occur elsewhere in the body. Treatment often includes surgery and radiation therapy, depending on the size and location of the tumor and how quickly it is growing.

Leiomyosarcoma

Leiomyosarcoma is an aggressive cancer that develops from smooth muscles, the muscles of the body that you cannot control. These tumors can be found anywhere smooth muscle exists, including the lining of the gastrointestinal tract, a woman’s uterus, and the lining of blood vessels, usually veins.

Leiomyosarcoma of the uterus is sometimes mistaken for a noncancerous tumor called leiomyoma. Surgically removing a suspected leiomyoma using a procedure called a morcellation, in which small pieces of the growth are removed one at a time, can inadvertently cause the spread, or seeding, of what is actually a leiomyosarcoma.

The chemotherapy drugs prescribed for leiomyosarcoma are different from those used for other soft tissue sarcomas, requiring the guidance of our medical oncologists.

Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans, also called DFSP, is a slow growing tumor consisting of long, narrow cells with tapered ends. Because of their appearance, doctors call them spindle cells. These tumors form in the skin or just below it, and surgery can lead to a remission.

The development of dermatofibrosarcoma protuberans is associated with the rearrangement—also known as translocation—of genetic material between two chromosomes, the structures that contain genes within the body’s cells.

Although DFSPs infrequently spread to other organs, they may recur in the area in which they originally grew, even if the border of tissue around the tumor was clear of cancer cells.

Low-Grade Fibromyxoid Sarcoma

Low-grade fibromyxoid sarcomas are slow growing but also have the potential to spread to other parts of the body many years after diagnosis. They can appear on the trunk, arms, or legs as a painless lump. These tumors contain a gene mutation, which doctors use to diagnose the cancer. Surgery can successfully treat the condition, but most of these tumors tend to come back after several years.

Malignant Peripheral Nerve Sheath Tumor

Malignant peripheral nerve sheath tumors are cancerous sarcomas that arise in the cells surrounding the nerves in the peripheral nervous system, meaning those outside the spinal cord and brain. This form of sarcoma can develop spontaneously or in people with a genetic condition called neurofibromatosis type 1, who can receive care at the NYU Langone Comprehensive Neurofibromatosis Center.

Symptoms of these tumors can include pain, weakness, or numbness in the muscles near the tumor. Treatment can include surgery, along with radiation therapy and chemotherapy.

Fibromatosis and Desmoid Tumors

Both fibromatosis and desmoid tumors are usually slow growing and benign, or noncancerous, sarcomas that do not spread. But some can grow fast and become large enough to damage surrounding vital organs, such as the intestines, liver, lungs, and nerves.

These tumors can occur spontaneously, meaning without any apparent reason, but they are more commonly associated with a genetic syndrome called familial adenomatous polyposis, or Gardner’s syndrome. They can also develop in the abdomen in pregnant women or in the arms, legs, hands, feet, or chest wall.

These tumors almost always come back after being removed with surgery alone. However, they may respond to hormone therapy, especially those that arise during pregnancy.

Targeted drugs, which are designed to destroy cancer cells while sparing much of the body’s healthy tissue, and chemotherapy may also be effective. Because they are benign tumors, NYU Langone doctors usually use the least toxic form of medications available. Medications are often given before surgery to help shrink the tumors, making the procedure safer and more effective.

Sometimes, doctors use radiation therapy to shrink growing desmoid tumors. Some desmoid tumors stop growing and shrink on their own without any treatment. These tumors are closely monitored by doctors.

Gastrointestinal Stromal Tumor

Gastrointestinal stromal tumors develop from cells that line the gastrointestinal tract wall and are part of the autonomic nervous system, meaning the cells automatically regulate processes in the body such as helping to digest food. Most of these tumors develop in the stomach or small intestine and may cause nausea, diarrhea, or abdominal swelling or discomfort.

In addition to surgery, targeted medications can cause a remission in people who have a high risk of the cancer coming back.

Synovial Sarcoma

Synovial sarcoma can be aggressive, and doctors do not yet understand which type of cells these tumors develop from. They can occur in the limbs, hands, or feet but may appear anywhere in the body. Symptoms depend on the location of the sarcoma. Those that appear in the arms and legs may cause a painless lump, while those in the head and neck may cause trouble with swallowing.

Synovial sarcomas are usually treated with chemotherapy first, followed by surgery. The addition of chemotherapy to surgery has greatly increased the remission rate for this tumor. NYU Langone doctors developed this treatment approach.

Alveolar Soft Part Sarcoma

Alveolar soft part sarcoma is a rare, slow growing tumor that can spread to the lungs and then the brain. This cancer may be painless and cause no symptoms until it’s advanced. The legs and buttocks are the most common location of these tumors, although they may also occur on the head and neck.

The development of alveolar soft part sarcoma is associated with a rearrangement of the genetic material in the tumor cells’ chromosomes that doctors use to help diagnose the cancer.

Surgery can result in a remission, but some tumors may come back afterward and spread. Alveolar soft part sarcoma does not respond to chemotherapy, but targeted medications may help treat tumors that have spread.

Epithelioid Sarcoma

Epithelioid sarcoma is a rare, slow growing tumor that has the potential to spread to other parts of the body. It usually first develops on the forearms and hands, on or below the skin. Sometimes the growths can cause pain or tenderness. This cancer usually affects people 20 to 40 years old but can occur at any age.

Epithelioid sarcomas are often small when they are found but usually come back after treatment with surgery, unless a very wide border, or margin, of healthy tissue is also removed. This helps to ensure all of the cancer cells are taken out. About half of people with this type of sarcoma also have area lymph nodes—the small glands throughout the body that trap viruses, bacteria, and other foreign material—that contain cancer and need to be removed.

When these tumors occur in the upper arms or legs or in the trunk of the body, they are called proximal epithelioid sarcoma. These tend to occur in people older than 40.