What is the definition of Synovial Sarcoma?

Synovial sarcoma is a rare and aggressive soft tissue sarcoma. In the early stages of the condition, it may cause no noticeable signs or symptoms. However, as the tumor grows larger, affected people may notice a lump or swelling. In some cases, the tumor can limit range of motion or cause numbness and/or pain if it presses on nearby nerves. Although synovial sarcoma does not have a clearly defined cause, genetic factors are believed to influence the development of this disease. Cells in these tumors are usually characterized by the presence of a translocation involving chromosomes X and 18. This translocation is specific to synovial sarcoma and is often used to diagnose the condition. Treatment generally includes a combination of surgery, radiation therapy and/or chemotherapy.

What are the alternative names for Synovial Sarcoma?

  • Synovial cell sarcoma
  • Synovialosarcoma

What are the causes for Synovial Sarcoma?

The exact underlying cause of synovial sarcoma is poorly understood. However, studies show that a certain genetic change is identified in more than 90% of cases. More specifically, a translocation between chromosome X and chromosome 18 appears to play a role in the development of synovial sarcoma. This alteration is known as a somatic mutation because it only develops in some cells of the body during a person's lifetime and is not inherited.

Certain inherited conditions such as Li Fraumeni syndrome or neurofibromatosis type 1 are associated with an increased risk of developing synovial sarcoma and other forms of soft tissue sarcoma. Some studies suggest that exposure to radiation therapy and/or certain chemical carcinogens may also be risk factors for soft tissue sarcoma.

What are the symptoms for Synovial Sarcoma?

In the early stages of the condition, synovial sarcoma may cause no noticeable signs or symptoms. However, as the tumor grows larger, affected people may notice a lump or swelling. In some cases, the tumor can limit range of motion or cause numbness and/or pain if it presses on nearby nerves. The symptoms of synovial sarcoma can be mistaken for those of inflammation of the joints (arthritis) or other non-cancerous conditions that cause inflammation such as bursitis and synovitis.

What are the current treatments for Synovial Sarcoma?

The treatment of synovial sarcoma depends on the age of the person; the size and location of the tumor and the severity of the disease. The most common treatment is surgery to remove the entire tumor. In some cases, radiation therapy and/or chemotherapy may also be necessary before and/or after the surgery. When given before surgery, radiation therapy and chemotherapy may reduce the size of the tumor, allowing less tissue to be removed. These therapies may be given after surgery to reduce the risk of recurrence.

The National Cancer Institute's Web site offers more specific information regarding the treatment and management of synovial sarcoma and other forms of soft tissue sarcoma. Please click on the link to access this resource.

What is the outlook (prognosis) for Synovial Sarcoma?

The long-term outlook (prognosis) for people with synovial sarcoma depends on many factors, including the size, grade and stage of the tumor; where the tumor is located; and the affected person's age and overall health. In general, synovial sarcoma has a survival rate of 50-60% at 5 years and 40-50% at 10 years. Recurrence has been reported up to 69 months after treatment and suggests a worse prognosis with low survival rates.

How is Synovial Sarcoma diagnosed?

A diagnosis of synovial sarcoma may first be suspected based on the presence of characteristic signs and symptoms. Additional testing can then be ordered to confirm the diagnosis, determine the severity of the condition and inform treatment options. These tests may include:
  • Imaging studies such as x-ray, CT scan and/or MRI scan
  • Genetic testing to detect the specific chromosomal translocation between chromosome 18 and chromosome X that is identified in most cases of synovial sarcoma
  • A biopsy of the tumor

Medscape Reference's Web site offers more specific information regarding the diagnosis of synovial sarcoma. Please click on the link to access this resource.

Is Synovial Sarcoma an inherited disorder?

Most cases of synovial sarcoma are not thought to be inherited. It generally occurs sporadically in people with no family history of the condition.

Rarely, synovial sarcoma and other types of soft tissue sarcoma are associated with an inherited condition such as Li Fraumeni syndrome or neurofibromatosis type 1, which are both inherited in an autosomal dominant manner. In autosomal dominant conditions, a person only needs a change (mutation) in one copy of the responsible gene in each cell to have a genetic predisposition to the sarcomas and other types of tumors. In some cases, an affected person inherits the mutation from an affected parent. Other cases may result from new (de novo) mutations in the gene. These cases occur in people with no history of the disorder in their family. A person with one of these conditions has a 50% chance with each pregnancy of passing along the altered gene to his or her child.
  • Condition: Brain Metastasis from Soft Tissue Sarcomas
  • Journal: Anticancer research
  • Treatment Used: Combined Surgery and Radiotherapy
  • Number of Patients: 509
  • Published —
This study tested the safety and efficacy of using a combined surgery and radiotherapy regimen to treat patients with brain metastases that they acquired from their soft tissue sarcoma.
  • Condition: Epithelioid Sarcoma
  • Journal: The Lancet. Oncology
  • Treatment Used: Tazemetostat
  • Number of Patients: 62
  • Published —
This study evaluated the safety and effectiveness of Tazemetostat, an oral selective EZH2 inhibitor, in patients with epithelioid sarcoma.
Clinical Trial
  • Status: Not yet recruiting
  • Intervention Type: Other, Diagnostic Test, Drug
  • Participants: 100000
  • Start Date: April 5, 2021
The Registry of Oncology Outcomes Associated With Testing and Treatment (ROOT)