Key Points for This Section

Adult soft tissue sarcoma is a disease in which malignant (cancer) cells form in the soft tissues of the body. Having certain inherited disorders can increase the risk of developing adult soft tissue sarcoma. Possible signs of adult soft tissue sarcoma include a lump or swelling in soft tissue of the body. Adult soft tissue sarcoma is diagnosed with a biopsy. Certain factors affect treatment options and prognosis (chance of recovery).

Adult soft tissue sarcoma is a disease in which malignant (cancer) cells form in the soft tissues of the body.

The soft tissues of the body include the muscles, tendons (bands of fiber that connect muscles to bones), fat, blood vessels, lymph vessels, nerves, and tissues around joints. Adult soft tissue sarcomas can form almost anywhere in the body, but are most common in the legs, abdomen, arms, and trunk.

There are many types of soft tissue sarcoma. One type that forms in the wall of the stomach, intestines, or rectum is called a gastrointestinal stromal tumor (GIST). The cells of each type of sarcoma look different under a microscope, based on the type of soft tissue in which the cancer began.

Having certain inherited disorders can increase the risk of developing adult soft tissue sarcoma.

Anything that increases your risk of getting a disease is called a risk factor. Risk factors for soft tissue sarcoma include the following inherited disorders:

• Retinoblastoma.
• Neurofibromatosis type 1 (von Recklinghausen disease or NF1).
• Tuberous sclerosis.
• Familial adenomatous polyposis (FAP).
• Li-Fraumeni syndrome.
• Werner syndrome.
• Basal cell nevus syndrome.

Other risk factors for soft tissue sarcoma include past treatment with radiation therapy during childhood or for the following types of cancer:

• Retinoblastoma.
• Breast cancer.
• Lymphoma.
• Cervical cancer.

Possible signs of adult soft tissue sarcoma include a lump or swelling in soft tissue of the body.

A sarcoma may appear as a painless lump under the skin, often on an arm or a leg. Sarcomas that begin in the abdomen may not cause symptoms until they become very large. As the sarcoma grows larger and presses on nearby organs, nerves, muscles, or blood vessels, symptoms may include:

• Pain.
• Trouble breathing.

Other conditions may cause the same symptoms that soft tissue sarcomas do. A doctor should be consulted if any of these problems occur.

Adult soft tissue sarcoma is diagnosed with a biopsy.

If a soft tissue sarcoma is suspected, a biopsy will be done. The type of biopsy that is done will be based on the size and location of the tumor. There are two types of biopsy that may be used:

• Incisional biopsy: The removal of part of a lump or a sample of tissue.
• Core biopsy: The removal of tissue using a wide needle.

Samples will be taken from the primary tumor, lymph nodes, and other suspicious areas. A pathologist views the tissue under a microscope to look for cancer cells and to find out the grade of the tumor. The grade of a tumor depends on how abnormal the cancer cells look under a microscope and how quickly the cells are dividing. High-grade tumors usually grow and spread more quickly than low-grade tumors. Because soft tissue sarcoma can be hard to diagnose, patients should ask to have biopsy samples checked by a pathologist who has experience in diagnosing soft tissue sarcoma.

Certain factors affect treatment options and prognosis (chance of recovery).

The treatment options and prognosis (chance of recovery) depend on the following:

• The type of soft tissue sarcoma.
• The size, grade, and stage of the tumor.
• Where the tumor is in the body.
• Whether the entire tumor is removed by surgery.
• The patient's age and general health.
• Whether the cancer has recurred (come back).

Glossary Terms

The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.

Not normal. An abnormal lesion or growth may be cancerous, premalignant (likely to become cancer), or benign.

A genetic condition that causes unusual facial features and disorders of the skin, bones, nervous system, eyes, and endocrine glands. People with this syndrome have a higher risk of basal cell carcinoma. Also called Gorlin syndrome and nevoid basal cell carcinoma syndrome.

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

Tissue removed from the body and examined under a microscope to determine whether disease is present.

A tube through which the blood circulates in the body. Blood vessels include a network of arteries, arterioles, capillaries, venules, and veins.

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

Cancer that forms in tissues of the cervix (the organ connecting the uterus and vagina). It is usually a slow-growing cancer that may not have symptoms but can be found with regular Pap tests (a procedure in which cells are scraped from the cervix and looked at under a microscope).

The removal of a tissue sample with a wide needle for examination under a microscope.

The process of identifying a disease, such as cancer, from its signs and symptoms.

In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

An inherited condition in which numerous polyps (growths that protrude from mucous membranes) form on the inside walls of the colon and rectum. It increases the risk of colorectal cancer. Also called familial polyposis and FAP.

A type of tumor that usually begins in cells in the wall of the gastrointestinal tract. It can be benign or malignant. Also called GIST.

The grade of a tumor depends on how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread. Grading systems are different for each type of cancer.

When referring to cancerous and precancerous growths, a term used to describe cells that look abnormal under a microscope. These cells are more likely to grow and spread quickly than cells in low-grade cancerous and precancerous growths.

A surgical procedure in which a portion of a lump or suspicious area is removed for diagnosis. The tissue is then examined under a microscope.

Transmitted through genes that have been passed from parents to their offspring (children).

The long, tube-shaped organ in the abdomen that completes the process of digestion. The intestine has two parts, the small intestine and the large intestine. Also called bowel.

A rare, inherited predisposition to multiple cancers, caused by an alteration in the p53 tumor suppressor gene.

When referring to cancerous and precancerous growths, a term used to describe cells that look nearly normal under a microscope. These cells are less likely to grow and spread quickly than cells in high-grade cancerous or precancerous growths.

A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.

A thin tube that carries lymph (lymphatic fluid) and white blood cells through the lymphatic system. Also called lymphatic vessel.

Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One kind is Hodgkin lymphoma, which is marked by the presence of a type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin lymphomas can be further divided into cancers that have an indolent (slow-growing) course and those that have an aggressive (fast-growing) course. These subtypes behave and respond to treatment differently. Both Hodgkin and non-Hodgkin lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer.

A bundle of fibers that receives and sends messages between the body and the brain. The messages are sent by chemical and electrical changes in the cells that make up the nerves.

A rare genetic condition that causes brown spots and tumors on the skin, freckling in skin areas not exposed to the sun, tumors on the nerves, and developmental changes in the nervous system, muscles, bone, and skin. Also called NF1.

A part of the body that performs a specific function. For example, the heart is an organ.

A doctor who identifies diseases by studying cells and tissues under a microscope.

The original tumor.

The likely outcome or course of a disease; the chance of recovery or recurrence.

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

The last several inches of the large intestine closest to the anus.

To come back or to return.

Cancer that forms in the tissues of the retina (the light-sensitive layers of nerve tissue at the back of the eye). Retinoblastoma usually occurs in children younger than 5 years. It may be hereditary or nonhereditary (sporadic).

Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

A cancer of the bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.

Refers to muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.

A cancer that begins in the muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body.

The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body.

An organ that is part of the digestive system. The stomach helps digest food by mixing it with digestive juices and churning it into a thin liquid.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

A set of symptoms or conditions that occur together and suggest the presence of a certain disease or an increased chance of developing the disease.

Tough, fibrous, cord-like tissue that connects muscle to bone or another structure, such as an eyeball. Tendons help the bone or structure to move.

A group or layer of cells that work together to perform a specific function.

A genetic disorder in which benign (noncancerous) tumors form in the kidneys, brain, eyes, heart, lungs, and skin. This disease can cause seizures, mental disabilities, and different types of skin lesions.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous). Also called neoplasm.