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

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General information about soft tissue sarcoma (clickhere)

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6.1. Risks of developing soft tissue sarcoma in children

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The presence of certain diseases and hereditary disorders can increase the risk of developing soft tissue sarcoma in children.

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Anything that increases the risk of a disease is called a risk factor. Having a risk factor does not mean you will get cancer; the absence of risk factors does not mean that you will not get cancer. Talk to your child's doctor if you think your child may be at risk.

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Risk factors for soft tissue sarcoma in children include the presence of the following inherited conditions:

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• Li-Fraumeni syndrome.

• Familial adenomatous polyposis (FAP).

• Changes in the RB1 gene.

• Changes in the SMARCB1 (INI1) gene.

• Neurofibromatosis type 1 (NF1).

• Werner syndrome.

• Tuberous sclerosis.

• Severe combined immunodeficiency with adenosine deaminase deficiency.

 

Other risk factors include the following:

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• Past treatment with radiation therapy.

• Sick of AIDS (acquired immunodeficiency syndrome) and Epstein-Barr virus infection at the same time.

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6.2. Symptoms 

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The most common symptom of childhood soft tissue sarcoma is a painless swelling or swelling in the soft tissues of the body.

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Sarcomas may appear as a painless lump under the skin, often on the arm, leg, chest, or abdomen. At first, there may be no other signs or symptoms. As the sarcoma gets larger and presses on nearby organs, nerves, muscles, or blood vessels, it may cause signs or symptoms, such as pain or weakness.

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Other conditions may cause the same signs and symptoms. Check with your child's doctor if your child has any of these concerns.

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6.3. Diagnosis 

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The following tests and procedures may be used:

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• Medical examination and health history:examining the body to check for general signs of health, including checking for signs of disease such as tumors or anything else that seems unusual. An anamnesis of the patient's health habits as well as past illnesses and treatments will also be taken.

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• X-rays :X-rays are a type of energy beam that can pass through the body onto film, taking pictures of areas inside the body.

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• MRI (magnetic resonance imaging) :a procedure that uses a magnet, radio waves, and a computer to create a series of detailed pictures of areas of the body, such as the chest, abdomen, arms, or legs. This procedure is also called nuclear magnetic resonance imaging (NMRI).

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• CT (computed tomography) :a procedure in which a series of detailed pictures of areas inside the body, such as the chest or abdomen, are taken from different angles. The pictures were taken by a computer connected to an x-ray machine. The dye may be injected into a vein or swallowed to make organs or tissues show more clearly. This procedure is also called computed tomography, computed tomography, or computed axial tomography.

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• Ultrasound procedure :a procedure in which high-energy sound waves (ultrasound) bounce off internal tissues or organs and create an echo. The echo forms a picture of body tissues called a sonogram. The picture can be printed to view later.

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If tests show that there may be a soft tissue sarcoma, a biopsy is performed.

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The type of biopsy depends in part on the size of the growth and whether it is close to the surface of the skin or deeper in the tissue. One of the following types of biopsy is usually used:

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• Core needle biopsy:removal of tissue with a wide needle. Several tissue samples are taken. This procedure can be guided by ultrasound, computed tomography, or MRI.

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• Postoperative biopsy:removal of part of the tumor or tissue sample.

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• Excision biopsy :removal of the entire tumor or an area of tissue that does not look normal. A pathologist examines tissue under a microscope for the presence of cancer cells. An excisional biopsy can be used to completely remove smaller tumors near the surface of the skin. This type of biopsy is rarely used because cancer cells may remain after the biopsy. If cancer cells remain, the cancer may return or spread to other parts of the body.

 

An MRI of the tumor is performed before the excisional biopsy. This is done to show where the original tumor formed and can be used to guide future surgery or radiation therapy.

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Whenever possible, the surgeon who removes any tumor found should be involved in planning the biopsy. The placement of biopsy needles or incisions may affect the ability to remove the entire tumor during later surgery.

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To plan the best treatment, the tissue sample taken during the biopsy must be large enough to determine the type of soft tissue sarcoma and perform other laboratory tests. Tissue samples will be taken from the primary tumor, lymph nodes, and other areas that may have cancer cells. The pathologist examines the tissue under a microscope to look for cancer cells and determine the type and grade of the tumor. The extent of the tumor depends on how abnormal the cancer cells look under the microscope and how quickly the cells divide. High- and intermediate-grade tumors usually grow and spread faster than low-grade tumors.

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Because soft tissue sarcoma is difficult to diagnose, the tissue sample should be reviewed by a pathologist experienced in diagnosing soft tissue sarcoma.

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One or more of the following laboratory tests may be performed to study tissue samples:

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• Molecular test :a laboratory test to check for certain genes, proteins, or other molecules in a sample of tissue, blood, or other body fluid. A molecular test may be done with other procedures, such as a biopsy, to help diagnose some types of cancer. Molecular tests check for certain gene or chromosomal changes that occur in some soft tissue sarcomas.

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• Reverse transcription polymerase chain reaction (RT-PCR) test :a laboratory test that measures the amount of a genetic substance called mRNA made by a particular gene. An enzyme called reverse transcriptase is used to convert a specific piece of RNA into a matching piece of DNA that can be amplified (done in large quantities) by another enzyme called DNA polymerase. Amplified DNA copies help determine if a particular mRNA is being created by a genome. RT-PCR can be used to check for the activation of certain genes that may indicate the presence of cancer cells. This test can be used to look for specific changes in a gene or chromosome that can help diagnose cancer.

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• Cytogenetic analysis:a laboratory test in which the chromosomes of cells in a sample of tumor tissue are counted and checked for any changes, such as broken, missing, rearranged, or extra chromosomes. Changes in some chromosomes can be a sign of cancer. Cytogenetic analysis is used to diagnose cancer, plan treatment, or determine the effectiveness of a treatment. Fluorescence in situ hybridization (FISH) is a type of cytogenetic analysis.

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• Immunocytochemistry:a laboratory test that uses antibodies to test for specific antigens (markers) in a sample of a patient's cells. The antibodies are usually associated with an enzyme or fluorescent dye. After the antibodies bind to the antigen in the patient's cell sample, the enzyme or dye is activated and the antigen can be seen under a microscope. This type of test can be used to tell the difference between different types of soft tissue sarcoma.

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• Light and electron microscopy:a laboratory test in which the cells in a tissue sample are looked at under a conventional and powerful microscope to look for specific changes in the cells.

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After being diagnosed with soft tissue sarcoma in childhood, tests are done to see if the cancer cells have spread to other parts of the body.

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The process used to determine if cancer has spread to soft tissues or to other parts of the body is called staging. There is no standard staging system for soft tissue sarcoma in children.

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To plan treatment, it is important to know the type of soft tissue sarcoma, whether the tumor can be surgically removed, and whether the cancer has spread to other parts of the body.

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To find out if the cancer has spread, the following procedures can be used:

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• Sentinel lymph node biopsy:removal of the sentinel lymph node during surgery. The sentinel lymph node is the first lymph node in the lymph node group to receive lymphatic drainage from the primary tumor. This is the first lymph node to which cancer can spread from the primary tumor. A radioactive substance and/or a blue dye is injected near the tumor. The substance or dye flows through the lymphatic pathways to the lymph nodes. The first lymph node to receive the substance or dye is removed. A pathologist examines tissue under a microscope to look for cancer cells. If no cancer cells are found, it may not be necessary to remove additional lymph nodes. Sometimes a sentinel lymph node is found in more than one group of nodes. This procedure is used for epithelioid and clear cell sarcomas.

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• CT (computed tomography) :a procedure that takes a series of detailed pictures of areas inside the body, such as the chest, taken from different angles. The pictures were taken by a computer connected to an x-ray machine. The dye can be injected into a vein or swallowed to make organs or tissues more clearly visible. This procedure is also called computed tomography, computed tomography, or computed axial tomography.

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• PET scan :A PET scan is a procedure to detect malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and takes a picture of where glucose is being used in the body. The cells of malignant tumors appear brighter in the picture because they are more active and consume more glucose than normal cells. This procedure is also called a positron emission tomography (PET) scan.

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• PET-CT scan :a procedure that combines PET scan and computed tomography (CT) images. PET and CT scans are performed simultaneously on the same machine. The images from both scans are combined to give a more detailed picture than either test could do on its own.

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6.4. Types of soft tissue sarcoma tumors in children

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There are many different types of soft tissue sarcomas.

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Cells of each type of sarcoma look different under a microscope. Soft tissue tumors are grouped according to the type of soft tissue cells in which they first formed.

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This summary is about the following types of soft tissue sarcomas:

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Tumors of adipose tissue

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Liposarcoma. This is a cancer of the fat cells. Liposarcoma usually forms in the fatty layer just under the skin. In children and adolescents, liposarcoma is often of low severity (it is likely to grow and spread slowly). There are several different types of liposarcomas, including:

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• Myxoid liposarcoma . It is usually a low-grade cancer that responds well to treatment.

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• Pleomorphic liposarcoma . It is usually a high-grade cancer that is less likely to be cured.

 

Tumors of bones and cartilage

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Bone and cartilage tumors are a mixture of bone and cartilage cells. Tumors of bones and cartilage are of the following types:

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• Extraskeletal mesenchymal chondrosarcoma. This type of bone and cartilage tumor often affects young people and occurs in the head and neck. It is usually highly malignant (can grow rapidly) and can spread to other parts of the body. It may also return many years after treatment.

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• Extraskeletal osteosarcoma . This type of bone and cartilage tumor is very rare in children and adolescents. It will likely return after treatment and may spread to the lungs.

 

Tumors of fibrous (connective) tissue

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Fibrous (connective tissue) tumors include the following types:

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• Desmoid fibromatosis (also called desmoid tumor or aggressive fibromatosis). This is a low grade fibrous tissue tumor (likely to grow slowly). It may return to nearby tissues but does not usually spread to distant parts of the body. Sometimes fibromatosis of the desmoid type can stop growing for a long time. In rare cases, the tumor may disappear without treatment.

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Children sometimes develop desmoid tumors with a change in the APC gene. Changes in this gene can also cause familial adenomatous polyposis (FAP). FAP is a hereditary disease (passed from parents to offspring) in which many polyps (growths on mucous membranes) form on the inner walls of the colon and rectum. Genetic counseling may be required (discussing hereditary diseases and genetic testing options with a trained specialist).

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• Protuberan dermatofibrosarcoma . This is a tumor of the deep layers of the skin, which most often forms in the trunk, arms or legs. The cells of this tumor have a specific genetic change called a translocation (part of the COL1A1 gene switches places with part of the PDGFRB gene). To diagnose protuberans dermatofibrosarcoma, tumor cells are tested for this genetic change. Dermatofibrosarcoma protuberance usually does not spread to the lymph nodes or other parts of the body.

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• Inflammatory myofibroblastic tumor . This cancer is made up of muscle cells, connective tissue cells, and certain immune cells. It occurs in children and adolescents. It forms most commonly in the soft tissues, lungs, spleen, and breasts. It often returns after treatment but rarely spreads to distant parts of the body. Some genetic variation has been found in about half of these tumors.

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• Fibrosarcoma.

  • Pediatric fibrosarcoma (also called congenital fibrosarcoma). This type of fibrosarcoma usually occurs in children 1 year of age and younger and can be detected on prenatal ultrasound. This tumor grows rapidly and is often large at diagnosis. It rarely spreads to distant parts of the body. The cells of this tumor usually have some kind of genetic change called a translocation (part of one chromosome switches places with part of another chromosome). To diagnose childhood fibrosarcoma, tumor cells are tested for this genetic change. A similar tumor has been observed in older children, but it does not have the translocation that is often seen in younger children.

  • Fibrosarcoma in adults. This is the same type of fibrosarcoma that occurs in adults. The cells of this tumor do not have genetic changes characteristic of childhood fibrosarcoma. 

• There are two types of fibrosarcoma in children and adolescents:

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• Myxofibrosarcoma . It is a rare fibrous tissue tumor that is less common in children than in adults.

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• Low grade fibromyxoid sarcoma . It is a slow-growing tumor that forms deep in the arms or legs and mostly affects young and middle-aged people. The tumor may return many years after treatment and spread to the lungs and chest lining. Lifelong monitoring is required.

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• Sclerosing epithelioid fibrosarcoma. This is a rare tumor of fibrous tissue that grows rapidly. It may return and spread to other parts of the body years after treatment. Long-term follow-up is required.

 

Skeletal muscle tumors

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Skeletal muscles attach to bones and help the body move.

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• Rhabdomyosarcoma . Rhabdomyosarcoma is the most common soft tissue sarcoma in children 14 years of age and younger. (For more information, see PDQ summary for treatment of pediatric rhabdomyosarcoma.)

 

Smooth muscle tumors

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Smooth muscles line the interior of blood vessels and hollow internal organs such as the stomach, intestines, bladder, and uterus.

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• Leiomyosarcoma . This smooth muscle tumor has been linked to the Epstein-Barr virus in children who also have HIV or AIDS. Leiomyosarcoma may also form as a second cancer in survivors of hereditary retinoblastoma, sometimes many years after initial treatment for retinoblastoma.

 

So-called fibrohistiocytic tumors

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• Plexiform fibrohistiocytic tumor . It is a rare tumor that usually affects children and young adults. The tumor usually starts as a painless growth on or just below the skin of the arm, hand, or wrist. Rarely, it can spread to nearby lymph nodes or the lungs.

 

Tumors of the nerve sheaths

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The nerve sheath consists of protective layers of myelin that cover nerve cells that are not part of the brain or spinal cord. Nerve sheath tumors are of the following types:

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• Malignant tumor of the peripheral nerve sheath. Some children with peripheral nerve sheath cancer have a rare genetic disorder called neurofibromatosis type 1 (NF1). This tumor can be low grade or high grade.

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• Malignant newt tumor. These are very fast growing tumors that most often occur in children with NF1.

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• Ectomesenchymoma . It is a fast growing tumor that occurs mainly in children. Ectomesenchymomas can form in the eye socket, abdomen, arms, or legs.

 

Pericytic (perivascular) tumors

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Pericytic tumors form in cells that surround blood vessels. Pericytic tumors are of the following types:

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• Myopericytoma . Pediatric hemangiopericytoma is a type of myopericytoma. Children younger than 1 year of age at diagnosis may have a better prognosis. In patients older than 1 year, infantile hemangiopericytoma is more likely to spread to other parts of the body, including the lymph nodes and lungs.

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• Childhood myofibromatosis. Children's myofibromatosis is another type of myopericytoma. This is a fibrous tumor that often forms in the first 2 years of life. There may be a single nodule under the skin, usually in the head and neck (myofibroma), or multiple nodules in the skin, muscles, or bones (myofibromatosis). In patients with infantile myofibromatosis, the cancer can also spread to organs. These tumors may disappear without treatment.

 

Tumors of unknown cellular origin

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Tumors of unknown cellular origin (the type of cell in which the tumor first formed is unknown) include the following types:

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• Synovial sarcoma . Synovial sarcoma is a common type of soft tissue sarcoma in children and adolescents. It usually forms in the tissues around the joints of the arms or legs, but it can also form in the trunk, head, or neck. The cells of this tumor usually have some kind of genetic change called a translocation (part of one chromosome switches places with part of another chromosome). Larger tumors have a greater risk of spreading to other parts of the body, including the lungs. Children younger than 10 years of age who have a tumor that is 5 centimeters or smaller in the arms or legs have a better prognosis.

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• Epithelioid sarcoma . This is a rare sarcoma that usually starts deep in the soft tissues as a slowly growing hard lump and may spread to the lymph nodes. If cancer has formed in the arms, legs, or buttocks, a sentinel lymph node biopsy may be done to check for cancer in the lymph nodes.

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• Soft alveolar sarcomaparts . This is a rare tumor of soft, supportive tissue that connects and surrounds organs and other tissues. It most commonly occurs in the arms and legs, but can occur in the tissues of the mouth, jaws, and face. It can grow slowly and often spreads to other parts of the body. Soft alveolar sarcoma may have a better prognosis when the tumor is 5 centimeters or smaller, or when the tumor is completely removed by surgery. The cells of this tumor usually have a certain genetic change called a translocation (part of the ASSPL gene switches places with part of the TFE3 gene). To diagnose soft alveolar sarcoma, tumor cells are tested for this genetic change.

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• Soft tissue clear cell sarcoma . It is a slow-growing soft tissue tumor that starts in a tendon (tough, fibrous, umbilical cord tissue that connects a muscle to a bone or to another part of the body). Clear cell sarcoma most commonly occurs in the deep tissues of the foot, heel, and ankle. It can spread to nearby lymph nodes. The cells of this tumor usually have some kind of genetic change called a translocation (part of the EWSR1 gene switches places with part of the ATF1 or CREB1 gene). To diagnose clear cell soft tissue sarcoma, tumor cells are tested for this genetic change.

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• Extraskeletal myxoid chondrosarcoma. This type of soft tissue sarcoma can occur in children and adolescents. Over time, it tends to spread to other parts of the body, including the lymph nodes and lungs. The tumor may return many years after treatment.

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• Extraskeletal Ewing's sarcoma

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• Desmoplastic small cell tumor . This tumor most commonly forms in the peritoneum of the abdomen, pelvis, and/or peritoneum in the scrotum, but may form in the kidneys or other solid organs. Dozens of small tumors can form in the peritoneum. Desmoplastic small cell tumor can also spread to the lungs and other parts of the body. The cells of this tumor usually have some kind of genetic change called a translocation (part of one chromosome switches places with part of another chromosome). To diagnose a desmoplastic small cell tumor, tumor cells are tested for this genetic change.

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• Extrarenal (extracranial) rhabdoid tumor . This rapidly growing tumor forms in soft tissues such as the liver and bladder. It usually occurs in young children, including newborns, but may occur in older children and adults. Rhabdoid tumors may be associated with a change in a tumor suppressor gene called SMARCB1. This type of gene makes a protein that helps control cell growth. Changes in the SMARCB1 gene can be inherited. Genetic counseling may be required (discussion with a qualified specialist of hereditary diseases and the possible need for genetic testing).

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• Perivascular epithelioid cell tumors (PEComas).  Benign PEComas can occur in children with an inherited condition called tuberous sclerosis. They occur in the stomach, intestines, lungs and urinary organs. PEComas grow slowly and most of them are unlikely.

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• Undifferentiated/unclassified sarcoma. These tumors usually occur in the bones or muscles that are attached to the bones and help the body move.

  • Undifferentiated pleomorphic sarcoma/malignant fibrous histiocytoma (high grade). This type of soft tissue tumor can form in parts of the body where patients have previously received radiation therapy, or as a second cancer in children with retinoblastoma. The tumor usually forms in the arms or legs and may spread to other parts of the body.

 

Tumors of blood vessels

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Blood vessel tumors include the following types:

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• Epithelioid hemangioendothelioma . Epithelioid hemangioendotheliomas can occur in children but are most common in adults between the ages of 30 and 50. They usually originate in the liver, lungs, or bones. They can be either fast growing or slow growing. In about a third of cases, the tumor spreads very quickly to other parts of the body.

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• Angiosarcoma of soft tissues. Soft tissue angiosarcoma is a rapidly growing tumor that forms in the blood or lymph vessels anywhere in the body. Most angiosarcomas are in or under the skin. Those found in deeper soft tissues may form in the liver, spleen, or lungs. They are very rare in children, who sometimes have more than one tumor in the skin or liver. In rare cases, childhood hemangioma can become soft tissue angiosarcoma. 

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Sometimes soft tissue sarcoma in children continues to grow or comes back after treatment.

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Progressive soft tissue sarcoma in children is a cancer that continues to grow, spread, or get worse. Progressive disease may be a sign that the cancer has become refractory to treatment.

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Recurrent soft tissue sarcoma in childrenis cancer that has recurred (come back) after treatment. The cancer could reappear in the same place or in other parts of the body.

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6.5. Factors affecting the prognosis of recovery

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Prognosis and treatment options depend on the following:

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• The part of the body where the tumor first formed.

• Size and grade of the tumor.

• type of soft tissue sarcoma.

• How deep is the tumor under the skin.

• Whether the tumor has spread to other parts of the body and where it has spread.

• The amount of tumor left after surgery to remove it.

• Whether radiation therapy was used to treat the tumor.

• Whether the cancer was just diagnosed or recurred (came back).

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6.6. Overview of treatment options for  children's soft tissue sarcoma

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There are various methods of treatment for patients with soft tissue sarcoma in childhood.

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A variety of treatments are available to patients with childhood soft tissue sarcoma. Some treatments are standard (currently used) and some are in clinical trials. A clinical trial of a treatment is a scientific study designed to help improve existing treatments or provide information about new treatments for cancer patients. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.

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Since childhood cancer is rare, participation in clinical trials should be considered. Some clinical trials are only open to patients who have not yet started treatment.

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Children with soft tissue sarcoma in childhood should be planned for treatment by a team of healthcare professionals who are experts in treating childhood cancer.

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Treatment will be overseen by a pediatric oncologist, a doctor who specializes in treating children with cancer. A pediatric oncologist works with other health care providers who are experts in treating children with soft tissue sarcoma and specialize in specific areas of medicine. This may be a pediatric surgeon who has special training in the removal of soft tissue sarcomas. The following specialists may also be included:

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• Pediatrician.

• Radiation Oncologist.

• Pediatric hematologist.

• Pediatric Nurse Specialist.

• Rehabilitation Specialist.

• Psychologist .

• Social worker .

• Children's Life Specialist.

 

Seven types of standard treatment are used:

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1. Operation

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If possible, an operation is performed to completely remove the soft tissue sarcoma. If the tumor is very large, radiation therapy or chemotherapy may be given first in order to shrink the tumor and reduce the amount of tissue that needs to be removed during surgery. This is called neoadjuvant (preoperative) therapy.

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The following types of surgical interventions can be used:

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• Wide local excision : removal of the tumor along with the normal tissue around it.

• Amputation :surgery to remove all or part of an arm or leg with cancer.

• Lymphadenectomy :removal of lymph nodes for cancer.

• Mohs surgery:a surgical procedure used to treat skin cancer. Individual layers of cancerous tissue are removed and examined under a microscope one at a time until all of the cancerous tissue has been removed. This type of surgery is used to treat protuberance dermatofibrosarcoma. It is also called Mohs micrographic surgery.

• Hepatectomy : surgery to remove all or part of the liver.

 

A second operation may be required for:

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• Removal of all remaining cancer cells.

• Check the area around where the tumor was removed for cancer cells and then remove more tissue if necessary.

 

If the cancer is in the liver, a hepatectomy and liver transplant (the liver is removed and replaced with a healthy one from a donor) may be done.

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After the doctor removes any tumors that can be seen during surgery, some patients may be given chemotherapy or radiation therapy after surgery to kill any remaining cancer cells. Treatment given after surgery to reduce the risk of cancer coming back is called adjuvant therapy.

 

2. Radiation therapy

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Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or prevent them from growing. There are two types of radiation therapy:

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• External Beam Therapy uses a device outside the body to direct radiation to an area of the body affected by cancer. Certain ways of delivering radiation therapy can help prevent radiation damage to nearby healthy tissue. This type of radiation therapy may include the following:

  • Stereotactic Body Radiation Therapy : Stereotactic Body Radiation Therapy is a type of external beam radiation therapy. Special equipment is used to position the patient in the same position for each radiation therapy session. Once a day for several days, the radiation machine delivers a larger than usual dose of radiation directly to the tumor. If the patient is in the same position for each treatment session, there is less damage to nearby healthy tissue. This procedure is also called stereotactic external beam radiation therapy and stereotactic radiation therapy.

  • Conformal radiotherapy:conformal radiation therapy is a type of external beam radiation therapy in which a computer creates a three-dimensional (3-D) image of the tumor and generates radiation beams that match the tumor. This allows a high dose of radiation to reach the tumor and cause less damage to nearby healthy tissue.

  • Intensity Modulated Radiation Therapy (IMRT): IMRT is a type of three-dimensional (3-D) radiation therapy that uses a computer to produce images of the size and shape of a tumor. Thin beams of radiation of different intensity (strength) are directed to the tumor at different angles. This type of external beam radiation therapy does less damage to nearby healthy tissue.

• Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires or catheters that are injected directly into or near the tumor.

 

Whether radiation therapy is given before or after cancer surgery depends on the type and stage of cancer being treated, the presence of any cancer cells after surgery, and the expected side effects of the treatment. External and internal radiation therapy is used to treat soft tissue sarcoma in children.

 

3. Chemotherapy

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Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells by either killing the cells or stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is injected directly into the cerebrospinal fluid, organ, or body cavity, such as the abdominal cavity, the drugs mainly target cancer cells in those areas (regional chemotherapy). Combination chemotherapy is the use of more than one anticancer drug.

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Hyperthermic Intraperitoneal Chemotherapy (HIPEC)is a type of treatment used during surgery that is being studied for desmoplastic small cell tumor. After the surgeon has removed as much of the tumor tissue as possible, warm chemotherapy is directed directly into the abdomen.

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Method of conducting chemotherapydepends on the type of soft tissue sarcoma being treated. Most types of soft tissue sarcomas do not respond to chemotherapy.

 

4. Surveillance

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Observation is closely monitoring the patient's condition without giving any treatment until signs or symptoms appear or change. Observation may be carried out when:

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• Complete removal of the tumor is not possible.

• There are no other treatments available.

• The tumor is unlikely to damage any vital organs.

 

Observation may be used to treat desmoid-type fibromatosis, childhood fibrosarcoma, PEComa, or epithelioid hemangioendothelioma.

 

5. Targeted therapy

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Targeted therapy is a type of treatment that uses drugs or other substances to target and target specific cancer cells. Targeted therapy usually causes less damage to normal cells than chemotherapy or radiation therapy.

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• Kinase inhibitors block an enzyme called a kinase (a type of protein).There are different types of kinases in the body that have different actions.

  • ALK inhibitors can stop the growth and spread of cancer. Crizotinib may be used to treat inflammatory myofibroblastic tumor, childhood fibrosarcoma, and soft tissue clear cell sarcoma.

  • Tyrosine kinase inhibitors (TKIs) block the signals necessary for tumor growth. Imatinib is used to treat protuberance dermatofibrosarcoma. Pazopanib may be used to treat desmoid-type fibromatosis, epithelioid hemangioendothelioma, and some types of recurrent and progressive soft tissue sarcoma. Sorafenib can be used to treat desmoid-type fibromatosis and epithelioid hemangioendothelioma. Sunitinib can be used to treat soft alveolar sarcoma. Larotrectinib is used to treat childhood fibrosarcoma. Ceritinib is used to treat inflammatory myofibroblastic tumor. Axitinib may be used to treat some types of advanced soft tissue sarcoma, including alveolar soft tissue sarcoma.

• mTOR inhibitors are a type of targeted therapy that stops a protein that helps cells divide and survive. mTOR inhibitors are used to treat recurrent desmoplastic small cell tumors, PEComas, and epithelioid hemangioendothelioma and are also being studied to treat malignant peripheral nerve sheath tumors. Sirolimus and temsirolimus are mTOR inhibitor therapies 

 

New types of tyrosine kinase inhibitors are being studied, such as:

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• Entrectinib and selitrectinib in childhood fibrosarcoma.

• Trametinib for epithelioid hemangioendothelioma.

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6. Immunotherapy

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Immunotherapy is a treatment that uses the patient's immune system to fight cancer. Substances produced by the body or produced in a laboratory are used to enhance, direct, or restore the body's natural defenses against cancer. This cancer treatment is a type of biological therapy.

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Interferon and immune checkpoint inhibitor therapy are types of immunotherapy.

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• Interferon prevents tumor cells from dividing and can slow tumor growth. It is used to treat epithelioid hemangioendothelioma.

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• Immune checkpoint inhibitor therapy: Some types of immune cells, such as T cells and some cancer cells, have certain proteins on their surface, called checkpoint proteins, that control immune responses. When cancer cells contain large amounts of these proteins, they will not be attacked and killed by T cells. Immune checkpoint inhibitors block these proteins, and the ability of T cells to kill cancer cells is increased.

  There are two types of immune checkpoint inhibitor therapy:

  • CTLA-4 inhibitor therapy: CTLA-4 is a protein on the surface of T cells that helps control the body's immune responses. When CTLA-4 attaches to another protein called B7 on a cancer cell, it stops the T cell from killing the cancer cell. CTLA-4 inhibitors attach to CTLA-4 and allow T cells to kill cancer cells. Ipilimumab is a type of CTLA-4 inhibitor that is being studied for the treatment of angiosarcoma.

  • PD-1 and PD-L1 inhibitor therapy: PD-1 is a protein on the surface of T cells that helps control the body's immune responses. PD-L1 is a protein found on some types of cancer cells. When PD-1 attaches to PD-L1, it stops the T cell from killing the cancer cell. PD-1 and PD-L1 inhibitors prevent the PD-1 and PD-L1 proteins from attaching to each other. This allows T cells to kill cancer cells. Pembrolizumab is a type of PD-1 inhibitor that is used to treat progressive and recurrent soft tissue sarcoma. Nivolumab is a type of PD-1 inhibitor that is being studied for the treatment of angiosarcoma. Atezolizumab is a type of PD-L1 inhibitor that is being studied for the treatment of soft alveolar sarcoma.

 

7. Other drug therapy

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Steroid therapy has an antitumor effect in inflammatory myofibroblastic tumors.

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hormone therapyis a cancer treatment that removes or blocks hormones and stops the growth of cancer cells. Hormones are substances produced by glands in the body and circulate in the bloodstream. Certain hormones can cause certain types of cancer to grow. If tests show that cancer cells have places where hormones can attach (receptors), drugs, surgery, or radiation therapy are used to reduce the production of hormones or block them from working. Antiestrogens (drugs that block estrogen), such as tamoxifen, may be used to treat desmoid-type fibromatosis. Prasterone is being studied for the treatment of synovial sarcoma.

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Non-steroidal anti-inflammatory drugs (NSAIDs) are drugs (such as aspirin, ibuprofen, and naproxen) commonly used to reduce fever, swelling, pain, and redness. When treating desmoid-type fibromatosis, an NSAID called sulindac can be used to help block the growth of cancer cells.

 

6.7. Treatment for soft tissue sarcoma in children can cause side effects.

 

Side effects from cancer treatment that begin after treatment and continue for months or years are called late effects. Late effects of cancer treatment may include:

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• physical problems.

• Changes in mood, feelings, thinking, learning, or memory.

• Second cancer (new types of cancer).

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6.8. Treatment options soft tissue sarcomas in children

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Tumors of adipose tissue

 

Liposarcoma

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Treatment for newly diagnosed liposarcoma may include the following:

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• Surgery to completely remove the tumor. If the cancer is not completely removed, a second operation may be done.

• Chemotherapy to shrink the tumor followed by surgery.

• Radiation therapy before or after surgery.

 

Tumors of bones and cartilage

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Extraskeletal mesenchymal chondrosarcoma

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Treatment for newly diagnosed extraskeletal mesenchymal chondrosarcoma may include the following:

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• Surgery to completely remove the tumor. Radiation therapy may be given before and/or after surgery.

• Chemotherapy followed by surgery. After surgery, chemotherapy is prescribed with or without radiation therapy.

 

Extraskeletal osteosarcoma

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Treatment for newly diagnosed extraskeletal osteosarcoma may include the following:

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• Surgery to completely remove the tumor followed by chemotherapy.

 

Fibrous (connective) tissue tumors

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Fibromatosis desmoid type

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Treatment for newly diagnosed desmoid-type fibromatosis may include the following:

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• Surveillance for asymptomatic tumors, tumors that cannot damage any vital organs, and tumors that cannot be completely removed by surgery.

• Chemotherapy for tumors that have not been completely removed by surgery or that have recurred.

• Targeted therapy (sorafenib or pazopanib).

• Non-steroidal anti-inflammatory drugs (NSAIDs) therapy.

• Antiestrogenic drug therapy.

• Surgery to completely remove the tumor.

• Radiation therapy .

• Clinical study on targeted therapy with an inhibitor of the NOTCH pathway.

 

Protuberan dermatofibrosarcoma

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Treatment for newly diagnosed protuberance dermatofibrosarcoma may include the following:

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• Surgery to completely remove the tumor, if possible. This may include the Mohs operation.

• Radiation therapy before or after surgery.

• Radiation therapy and targeted therapy (imatinib) if the tumor cannot be removed or has returned.

 

Inflammatory myofibroblastic tumor

 

Treatment for a newly diagnosed inflammatory myofibroblastic tumor may include the following:

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• Surgery to completely remove the tumor, if possible.

• Chemotherapy.

• Steroid therapy.

• Non-steroidal anti-inflammatory drugs (NSAIDs) therapy.

• Targeted therapy (crizotinib and ceritinib).

 

fibrosarcoma

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Pediatric fibrosarcoma

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Treatment for newly diagnosed childhood fibrosarcoma may include the following:

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• Surgery to remove the tumor, if possible, followed by follow-up.

• Surgery followed by chemotherapy.

• Chemotherapy to shrink the tumor followed by surgery.

• Targeted therapy (crizotinib and larotrectinib).

• A clinical trial that tests a sample of a patient's tumor for certain gene changes. The type of targeted therapy that will be administered to a patient depends on the type of gene change.

• Clinical trials of targeted therapies (larotrectinib, entrectinib, or selitrectinib).

 

Fibrosarcoma in adults

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Treatment for newly diagnosed fibrosarcoma in adults may include the following:

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• Surgery to completely remove the tumor, if possible.

• Myxofibrosarcoma

• Treatment for newly diagnosed myxofibrosarcoma may include the following:

• Surgery to completely remove the tumor.

 

Fibromyxoid sarcoma, low grade

 

Treatment for newly diagnosed low-grade fibromyxoid sarcoma may include the following:

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• Surgery to completely remove the tumor.

 

Sclerosing epithelioid fibrosarcoma

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Treatment for newly diagnosed sclerosing epithelioid fibrosarcoma may include the following:

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• Surgery to completely remove the tumor.

• Skeletal muscle tumors

• Rhabdomyosarcoma

 

Smooth muscle tumors

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Leiomyosarcoma

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Treatment for newly diagnosed leiomyosarcoma may include the following:

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• Chemotherapy.

 

So-called fibrohistiocytic tumors

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Plexiform fibrohistiocytic tumor

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Treatment for a newly diagnosed plexiform fibrohistiocytic tumor may include the following:

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• Surgery to completely remove the tumor.

 

Tumors of the nerve sheath

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Malignant tumor of the peripheral nerve sheath

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Treatment for a newly diagnosed malignant peripheral nerve sheath tumor may include the following:

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• Surgery to completely remove the tumor, if possible.

• Radiation therapy before or after surgery.

• Chemotherapy for tumors that cannot be removed surgically.

• A clinical trial that tests a sample of a patient's tumor for certain gene changes. The type of targeted therapy that will be administered to a patient depends on the type of gene change.

• Clinical trials of targeted therapy (ganetespib or sirolimus) for tumors that cannot be surgically removed.

• Clinical trials of targeted therapy (tazemetostat).

 

It is unclear whether radiation therapy or chemotherapy after surgery improves tumor response to treatment.

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Malignant triton tumor

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Newly diagnosed malignant newt tumors can be treated in the same way as rhabdomyosarcomas and include surgery, chemotherapy, or radiation therapy. It is unclear whether radiation therapy or chemotherapy improves tumor response to treatment.

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Ectomesenchymoma

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Treatment for a newly diagnosed ectomesenchymoma may include the following:

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• Surgery.

• Chemotherapy.

• Radiation therapy .

 

Pericytic (perivascular) tumors

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Pediatric hemangiopericytoma

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Treatment for newly diagnosed childhood hemangiopericytoma may include the following:

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• Chemotherapy.

 

Childhood myofibromatosis

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Treatment for newly diagnosed infantile myofibromatosis may include the following:

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• Combined chemotherapy.

 

Tumors of unknown cell origin (the place where the tumor first formed is unknown)

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synovial sarcoma

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Treatment for newly diagnosed synovial sarcoma may include the following:

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• Surgery. Radiation therapy and/or chemotherapy may be given before or after surgery.

• Chemotherapy.

• Stereotactic radiotherapy for tumors that have spread to the lungs.

• Clinical Research on Gene Therapy.

• Clinical Trials of Hormone Therapy.

 

Epithelioid sarcoma

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Treatment for newly diagnosed epithelioid sarcoma may include the following:

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• If possible, surgery to remove the tumor.

• Chemotherapy.

• Radiation therapy before or after surgery.

• Clinical study on targeted therapy (tazemetostat).

 

Sarcoma of the alveolar soft part

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Treatment for newly diagnosed soft alveolar sarcoma may include the following:

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• Surgery to completely remove the tumor, if possible.

• Radiation therapy before or after surgery if the tumor cannot be completely removed by surgery.

• Targeted therapy (sunitinib).

• Clinical study on targeted therapy (cediranib or sunitinib).

• Clinical trials of immunotherapy (atezolizumab).

 

Clear cell soft tissue sarcoma

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Treatment for newly diagnosed clear cell soft tissue sarcoma may include the following:

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• If possible, surgery to remove the tumor.

• Radiation therapy before or after surgery.

• Targeted therapy (crizotinib).

 

Extraskeletal myxoid chondrosarcoma

 

Treatment for newly diagnosed extraskeletal myxoid chondrosarcoma may include the following:

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• If possible, surgery to remove the tumor.

• Radiation therapy .

• Clinical study on targeted therapy (tazemetostat).

 

Extraskeletal Ewing's sarcoma

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• Four types of standard treatment are used:

  • Chemotherapy

  • Radiation therapy

  • Operation

  • High-dose chemotherapy with stem cell rescue

• New treatments are undergoing clinical trials.

  • Targeted Therapy

  • Immunotherapy

 

Desmoplastic small cell tumor

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There is no standard treatment for a newly diagnosed desmoplastic small round cell tumor. Treatment may include the following:

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• Surgery to completely remove the tumor, if possible.

• Surgery and Hyperthermic Intraperitoneal Chemotherapy.

• Chemotherapy followed by surgery.

• Radiation therapy .

• Chemotherapy and targeted therapy (temsirolimus) for recurrent tumors.

 

Extrarenal (extracranial) rhabdoid tumor

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Treatment for a newly diagnosed extrarenal (extracranial) rhabdoid tumor may include the following:

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• If possible, surgery to remove the tumor.

• Chemotherapy.

• Radiation therapy .

• A clinical trial that tests a sample of a patient's tumor for certain gene changes. The type of targeted therapy that will be administered to a patient depends on the type of gene change.

• Clinical trials of targeted therapy (tazemetostat).

 

Perivascular epithelioid cell tumors (PEComas)

 

Treatment for newly diagnosed perivascular epithelioid cell tumors may include the following:

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• Surgery to remove the tumor.

• Observation followed by surgery.

• Targeted therapy (sirolimus) for tumors that have certain genetic changes and cannot be removed by surgery.

 

Undifferentiated / unclassified sarcoma

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Undifferentiated pleomorphic sarcoma/malignant fibrous histiocytoma (high grade)

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There is no standard treatment for these tumors.

 

Tumors of blood vessels

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Epithelioid hemangioendothelioma

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Treatment for newly diagnosed epithelioid hemangioendothelioma may include the following:

• Observation.

• If possible, surgery to remove the tumor.

• Immunotherapy (interferon) and targeted therapy (thalidomide, sorafenib, pazopanib, sirolimus) for tumors that can spread.

• Chemotherapy.

• Total hepatectomy and liver transplantation for liver tumors.

• Clinical study on targeted therapy ( trametinib ).

 

Soft tissue angiosarcoma

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Treatment for newly diagnosed angiosarcoma may include the following:

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• Surgery to completely remove the tumor.

• Combination of surgery, chemotherapy and radiotherapy for advanced angiosarcoma.

• Targeted therapy (bevacizumab) and chemotherapy for angiosarcomas that started as infantile hemangiomas.

• Clinical trial of chemotherapy with or without targeted therapy (Pazopanib).

• Clinical trials for immunotherapy (nivolumab and ipilimumab).

 

Metastatic soft tissue sarcoma in children

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Treatment for childhood soft tissue sarcoma that has spread to other parts of the body at diagnosis may include the following:

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• Chemotherapy and Radiation Therapy. Surgery may be done to remove tumors that have spread to the lung.

• Stereotactic radiotherapy for tumors that have spread to the lungs.

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Treatment of progressive or recurrent soft tissue sarcoma in children

 

Treatment for advanced or recurrent soft tissue sarcoma in children may include the following:

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• Surgery to remove cancer that has returned to where it first formed or has spread to the lungs.

• Surgery followed by external or internal radiation therapy, if radiation therapy has not yet been performed.

• Surgery to remove the cancerous arm or leg if radiation therapy has already been given.

• Surgical treatment of recurrent synovial sarcoma with or without chemotherapy.

• Chemotherapy.

• Targeted therapy (Pazopanib or axitinib).

• Immunotherapy (pembrolizumab).

• Stereotactic radiation therapy to treat cancer that has spread to other parts of the body, especially the lungs.

• Clinical trial of a new chemotherapy regimen with or without targeted therapy (Pazopanib).

• A clinical trial that tests a sample of a patient's tumor for certain gene changes. The type of targeted therapy that will be administered to a patient depends on the type of gene change.