Sarcoma Facts

January 22, 2026

This page was reviewed under our medical and editorial policy by Lee Cranmer, M.D., Ph.D., professor, Department of Medical Oncology & Therapeutics Research, City of Hope^® Cancer Center Duarte.

Sarcoma is a rare cancer that affects the bone or soft tissues. The American Cancer Society estimates that 13,910 people (7,840 males and 6,070 females) will be diagnosed with soft tissue sarcomas in 2026.

What Is Sarcoma?

Sarcomas are uncommon cancers that develop in a person’s connective tissues, including bone, cartilage, fat, muscle, nerves, blood vessels and lymph vessels. Connective tissues are like scaffolding in the body and give structure and support to other tissues and organs.

Sarcomas are typically divided into two main types, bone sarcomas and soft tissue sarcomas. There are many different types of each. Knowing the exact type of sarcoma disease that a patient is affected by is important in designing personalized treatment.

Sarcoma may affect both children and adults and may affect any bone or soft tissue of the body. The most common sarcomas include:

• Undifferentiated pleomorphic sarcoma, also known as malignant fibrous histiocytoma (forms in soft tissue or bones)
• Liposarcoma (forms in fatty tissue
• Leiomyosarcoma (forms in smooth muscle)
• Rhabdomyosarcoma, the most common type of soft tissue sarcoma in children (forms in muscle cells)

Common types of bone sarcomas include osteosarcoma (a sarcoma arising from the bone), and chondrosarcoma (a sarcoma arising in cartilage). Tumors typically form in the bones of the pelvis, legs or arms, but may form in any bone. Other bone sarcomas include Ewing sarcoma and many other less common types.

Which Body Parts Are Usually Affected?

Sarcomas may affect any of the bones or soft tissues of the body. In children and young adults, osteosarcoma typically begins in places where the bone is growing quickly, such as the lower thigh, upper shin or upper arm near the shoulder. In older adults, osteosarcoma is more likely to grow in the bones of the pelvis, jaw or shoulder.

Soft tissue sarcomas may grow anywhere in the body, but some locations are more likely to be affected. In the abdomen, liposarcomas and leiomyosarcomas are the most common types of sarcoma. Sometimes, it is difficult to identify the exact type of sarcoma that a person has. Doctors refer to these as “sarcomas of uncertain type.”

What Causes Sarcoma?

Researchers do not know what exactly causes sarcomas to develop. There are probably multiple factors contributing to the formation of these diseases.

Changes in DNA of cells underlies virtually all forms of cancer, including sarcomas. These alterations in DNA (mutations) disrupt the normal control mechanisms of cells, causing them to multiply or grow inappropriately and to spread (or metastasize) to more distant parts of the body.

These mutations may be inherited or acquired. Some people inherit mutations in their DNA that predispose them to develop cancers, including potential sarcomas. Other people acquire these mutations during their lifetimes. Various environmental exposures may lead to these alterations, including radiation, exposure to chemicals, and hormonal influences. That being said, in most cases, an exact cause is unknown.

Sarcoma Risk Factors

Certain factors may increase a person’s risk for developing sarcoma. Things that may raise a person’s risk for soft tissue sarcoma include the following.

Prior radiation therapy to treat other cancer: Sarcomas may start to grow in an area of the body that was treated with radiation in the past. On average, this may happen 10 years after the last radiation treatment. With the development of effective therapies to treat childhood cancers, adult survivors of childhood cancers may be at risk of developing cancers, including sarcomas, related to that treatment as a child.

Family cancer syndromes: Certain inherited gene mutations may increase a person’s risk for developing sarcomas. These include the following.

Gardner syndrome: People with this defect in the APC gene are more likely to develop polyps in the small intestine or colon and tumors in the soft tissue outside the colon.

Gorlin syndrome: People with this defect in the PTCH1 gene have a high risk for developing basal cell skin cancer, fibrosarcoma and rhabdomyosarcoma.

Li-Fraumeni syndrome: This is a defect in the TP53 gene that increases a person’s risk for developing brain tumors, breast cancer and lymphoma. People with Li-Fraumeni syndrome may be more sensitive to the cancer-causing effects of radiation treatments.

Neurofibromatosis: People with defects in the NF1 and NF2 genes may develop cancer in the nerves.

Retinoblastoma: Children with a defect in the RB1 gene may develop eye cancer and face a heightened risk for developing sarcoma after radiation treatment.

Tuberous sclerosis: Defects in the TSC1 or TSC2 gene may raise a person’s risk for developing rhabdomyosarcoma and kidney problems.

Werner syndrome: Children with defects in the RECQL2 gene have a greater risk for developing soft tissue sarcomas.

Exposure to certain chemicals: Certain chemicals may be linked to an increased risk for developing sarcomas, including vinyl chloride, arsenic, dioxin, certain herbicides and phenoxyacetic acid.

Lymph system damage: In rare cases, people with chronic lymphedema, a build-up of lymph fluid that often occurs in the arm or leg, may develop a type of sarcoma called lymphangiosarcoma.

Factors that may increase a person’s risk of bone sarcoma include the following.

Sex: Some sarcomas are more common in one sex than another. For example, osteosarcoma is more common in males than in females, although females may develop it sooner in life.

Age: The risk of different types of sarcomas varies over the lifespan. For example, people between the ages of 10 and 30 have the highest risk for osteosarcoma, and the risk is during periods of rapid growth such as the teenage years. Adults ages 60 years and older also have an increased risk for developing osteosarcoma due to bone disease.

Height: Being taller than usual for their age increases a person’s risk for osteosarcoma.

Ethnicity: African American, Latino and Hispanic children have a greater risk for developing osteosarcoma than white children.

Bone diseases: Having noncancerous bone disease, such as Paget’s disease, osteochondromas or fibrous dysplasia, may increase a person’s risk for osteosarcoma.

Is Sarcoma Hereditary?

While sarcoma usually occurs without a known hereditary reason, some people inherit family cancer syndromes that may increase the risk for developing sarcoma. These inherited diseases and syndromes include hereditary retinoblastoma, Li-Fraumeni syndrome, Rothmund-Thomson syndrome, Bloom syndrome, Werner syndrome and Diamond-Blackfan anemia.

Though people with these syndromes do not necessarily develop cancer, including sarcomas, they are at a much higher risk of doing so than non-affected persons. Knowing whether such a syndrome exists in a patient may be helpful in planning treatment, identifying other health risks and aiding family members as they aim to protect themselves.